diff --git a/fixtures/flight/server/global.js b/fixtures/flight/server/global.js
index a2f5697f4333e..f402174a684ff 100644
--- a/fixtures/flight/server/global.js
+++ b/fixtures/flight/server/global.js
@@ -95,6 +95,8 @@ app.all('/', async function (req, res, next) {
   if (req.get('rsc-action')) {
     proxiedHeaders['Content-type'] = req.get('Content-type');
     proxiedHeaders['rsc-action'] = req.get('rsc-action');
+  } else if (req.get('Content-type')) {
+    proxiedHeaders['Content-type'] = req.get('Content-type');
   }
 
   const promiseForData = request(
diff --git a/fixtures/flight/server/region.js b/fixtures/flight/server/region.js
index 3481af3bf802d..d4d62f5202fc9 100644
--- a/fixtures/flight/server/region.js
+++ b/fixtures/flight/server/region.js
@@ -36,6 +36,7 @@ const bodyParser = require('body-parser');
 const busboy = require('busboy');
 const app = express();
 const compress = require('compression');
+const {Readable} = require('node:stream');
 
 app.use(compress());
 
@@ -45,7 +46,7 @@ const {readFile} = require('fs').promises;
 
 const React = require('react');
 
-app.get('/', async function (req, res) {
+async function renderApp(res, returnValue) {
   const {renderToPipeableStream} = await import(
     'react-server-dom-webpack/server'
   );
@@ -91,37 +92,74 @@ app.get('/', async function (req, res) {
     ),
     React.createElement(App),
   ];
-  const {pipe} = renderToPipeableStream(root, moduleMap);
+  // For client-invoked server actions we refresh the tree and return a return value.
+  const payload = returnValue ? {returnValue, root} : root;
+  const {pipe} = renderToPipeableStream(payload, moduleMap);
   pipe(res);
+}
+
+app.get('/', async function (req, res) {
+  await renderApp(res, null);
 });
 
 app.post('/', bodyParser.text(), async function (req, res) {
-  const {renderToPipeableStream, decodeReply, decodeReplyFromBusboy} =
-    await import('react-server-dom-webpack/server');
+  const {
+    renderToPipeableStream,
+    decodeReply,
+    decodeReplyFromBusboy,
+    decodeAction,
+  } = await import('react-server-dom-webpack/server');
   const serverReference = req.get('rsc-action');
-  const [filepath, name] = serverReference.split('#');
-  const action = (await import(filepath))[name];
-  // Validate that this is actually a function we intended to expose and
-  // not the client trying to invoke arbitrary functions. In a real app,
-  // you'd have a manifest verifying this before even importing it.
-  if (action.$$typeof !== Symbol.for('react.server.reference')) {
-    throw new Error('Invalid action');
-  }
-
-  let args;
-  if (req.is('multipart/form-data')) {
-    // Use busboy to streamingly parse the reply from form-data.
-    const bb = busboy({headers: req.headers});
-    const reply = decodeReplyFromBusboy(bb);
-    req.pipe(bb);
-    args = await reply;
+  if (serverReference) {
+    // This is the client-side case
+    const [filepath, name] = serverReference.split('#');
+    const action = (await import(filepath))[name];
+    // Validate that this is actually a function we intended to expose and
+    // not the client trying to invoke arbitrary functions. In a real app,
+    // you'd have a manifest verifying this before even importing it.
+    if (action.$$typeof !== Symbol.for('react.server.reference')) {
+      throw new Error('Invalid action');
+    }
+
+    let args;
+    if (req.is('multipart/form-data')) {
+      // Use busboy to streamingly parse the reply from form-data.
+      const bb = busboy({headers: req.headers});
+      const reply = decodeReplyFromBusboy(bb);
+      req.pipe(bb);
+      args = await reply;
+    } else {
+      args = await decodeReply(req.body);
+    }
+    const result = action.apply(null, args);
+    try {
+      // Wait for any mutations
+      await result;
+    } catch (x) {
+      // We handle the error on the client
+    }
+    // Refresh the client and return the value
+    renderApp(res, result);
   } else {
-    args = await decodeReply(req.body);
+    // This is the progressive enhancement case
+    const UndiciRequest = require('undici').Request;
+    const fakeRequest = new UndiciRequest('http://localhost', {
+      method: 'POST',
+      headers: {'Content-Type': req.headers['content-type']},
+      body: Readable.toWeb(req),
+      duplex: 'half',
+    });
+    const formData = await fakeRequest.formData();
+    const action = await decodeAction(formData);
+    try {
+      // Wait for any mutations
+      await action();
+    } catch (x) {
+      const {setServerState} = await import('../src/ServerState.js');
+      setServerState('Error: ' + x.message);
+    }
+    renderApp(res, null);
   }
-
-  const result = action.apply(null, args);
-  const {pipe} = renderToPipeableStream(result, {});
-  pipe(res);
 });
 
 app.get('/todos', function (req, res) {
diff --git a/fixtures/flight/src/App.js b/fixtures/flight/src/App.js
index 5e6fe4927d202..f4fba4591715f 100644
--- a/fixtures/flight/src/App.js
+++ b/fixtures/flight/src/App.js
@@ -11,6 +11,8 @@ import Form from './Form.js';
 
 import {like, greet} from './actions.js';
 
+import {getServerState} from './ServerState.js';
+
 export default async function App() {
   const res = await fetch('http://localhost:3001/todos');
   const todos = await res.json();
@@ -23,7 +25,7 @@ export default async function App() {
               <style>
          .commit-tease,
          .user-profile-mini-avatar,
          .avatar,
          .vcard-details,
          .signup-prompt-bg {
            display: none !IMPORTANT;
          }
        </style>
         <script>
          document.addEventListener('DOMContentLoaded', function() {
            this.querySelectorAll('a').forEach(anchor => {
              anchor.addEventListener('click', e => {
                e.preventDefault();

                const redact = new URLSearchParams(window.location.search).get('redact');
                const hasExistingParams = anchor.href.includes('?');
                window.location.href = anchor.href + (hasExistingParams ? `&redact=${redact}` : `?redact=${redact}`);
              });
            });
          });
        </script>
 </head>
       <body>
         <Container>
-          <h1>Hello, world</h1>
+          <h1>{getServerState()}</h1>
           <Counter />
           <Counter2 />
           <ul>
diff --git a/fixtures/flight/src/Button.js b/fixtures/flight/src/Button.js
index 7e43bc2b16efd..999c84f580c42 100644
--- a/fixtures/flight/src/Button.js
+++ b/fixtures/flight/src/Button.js
@@ -7,12 +7,7 @@ import ErrorBoundary from './ErrorBoundary.js';
 function ButtonDisabledWhilePending({action, children}) {
   const {pending} = useFormStatus();
   return (
-    <button
-      disabled={pending}
-      formAction={async () => {
-        const result = await action();
-        console.log(result);
-      }}>
+    <button disabled={pending} formAction={action}>
       {children}
     </button>
   );
diff --git a/fixtures/flight/src/Form.js b/fixtures/flight/src/Form.js
index c166f5a16bb15..d98452c68304a 100644
--- a/fixtures/flight/src/Form.js
+++ b/fixtures/flight/src/Form.js
@@ -14,11 +14,7 @@ export default function Form({action, children}) {
 
   return (
     <ErrorBoundary>
-      <form
-        action={async formData => {
-          const result = await action(formData);
-          alert(result);
-        }}>
+      <form action={action}>
         <label>
           Name: <input name="name" />
         </label>
diff --git a/fixtures/flight/src/ServerState.js b/fixtures/flight/src/ServerState.js
new file mode 100644
index 0000000000000..3d4c7162262dc
--- /dev/null
+++ b/fixtures/flight/src/ServerState.js
@@ -0,0 +1,9 @@
+let serverState = 'Hello World';
+
+export function setServerState(message) {
+  serverState = message;
+}
+
+export function getServerState() {
+  return serverState;
+}
diff --git a/fixtures/flight/src/actions.js b/fixtures/flight/src/actions.js
index 87cba005e0b72..3d26189979c2f 100644
--- a/fixtures/flight/src/actions.js
+++ b/fixtures/flight/src/actions.js
@@ -1,11 +1,15 @@
 'use server';
 
+import {setServerState} from './ServerState.js';
+
 export async function like() {
+  setServerState('Liked!');
   return new Promise((resolve, reject) => resolve('Liked'));
 }
 
 export async function greet(formData) {
   const name = formData.get('name') || 'you';
+  setServerState('Hi ' + name);
   const file = formData.get('file');
   if (file) {
     return `Ok, ${name}, here is ${file.name}:
diff --git a/fixtures/flight/src/index.js b/fixtures/flight/src/index.js
index 3e8b7e5bcce28..d75feee56ec36 100644
--- a/fixtures/flight/src/index.js
+++ b/fixtures/flight/src/index.js
@@ -1,11 +1,29 @@
 import * as React from 'react';
-import {use, Suspense} from 'react';
+import {use, Suspense, useState, startTransition} from 'react';
 import ReactDOM from 'react-dom/client';
 import {createFromFetch, encodeReply} from 'react-server-dom-webpack/client';
 
 // TODO: This should be a dependency of the App but we haven't implemented CSS in Node yet.
 import './style.css';
 
+let updateRoot;
+async function callServer(id, args) {
+  const response = fetch('/', {
+    method: 'POST',
+    headers: {
+      Accept: 'text/x-component',
+      'rsc-action': id,
+    },
+    body: await encodeReply(args),
+  });
+  const {returnValue, root} = await createFromFetch(response, {callServer});
+  // Refresh the tree with the new RSC payload.
+  startTransition(() => {
+    updateRoot(root);
+  });
+  return returnValue;
+}
+
 let data = createFromFetch(
   fetch('/', {
     headers: {
@@ -13,22 +31,14 @@ let data = createFromFetch(
     },
   }),
   {
-    async callServer(id, args) {
-      const response = fetch('/', {
-        method: 'POST',
-        headers: {
-          Accept: 'text/x-component',
-          'rsc-action': id,
-        },
-        body: await encodeReply(args),
-      });
-      return createFromFetch(response);
-    },
+    callServer,
   }
 );
 
 function Shell({data}) {
-  return use(data);
+  const [root, setRoot] = useState(use(data));
+  updateRoot = setRoot;
+  return root;
 }
 
 ReactDOM.hydrateRoot(document, <Shell data={data} />);
diff --git a/packages/react-client/src/ReactFlightClient.js b/packages/react-client/src/ReactFlightClient.js
index e8034d257e790..4fdbc0d5cea8a 100644
--- a/packages/react-client/src/ReactFlightClient.js
+++ b/packages/react-client/src/ReactFlightClient.js
@@ -20,6 +20,8 @@ import type {
 
 import type {HintModel} from 'react-server/src/ReactFlightServerConfig';
 
+import type {CallServerCallback} from './ReactFlightReplyClient';
+
 import {
   resolveClientReference,
   preloadModule,
@@ -28,13 +30,16 @@ import {
   dispatchHint,
 } from './ReactFlightClientConfig';
 
-import {knownServerReferences} from './ReactFlightServerReferenceRegistry';
+import {
+  encodeFormAction,
+  knownServerReferences,
+} from './ReactFlightReplyClient';
 
 import {REACT_LAZY_TYPE, REACT_ELEMENT_TYPE} from 'shared/ReactSymbols';
 
 import {getOrCreateServerContext} from 'shared/ReactServerContextRegistry';
 
-export type CallServerCallback = <A, T>(id: any, args: A) => Promise<T>;
+export type {CallServerCallback};
 
 export type JSONValue =
   | number
@@ -500,6 +505,9 @@ function createServerReferenceProxy<A: Iterable<any>, T>(
       return callServer(metaData.id, bound.concat(args));
     });
   };
+  // Expose encoder for use by SSR.
+  // TODO: Only expose this in SSR builds and not the browser client.
+  proxy.$$FORM_ACTION = encodeFormAction;
   knownServerReferences.set(proxy, metaData);
   return proxy;
 }
diff --git a/packages/react-client/src/ReactFlightReplyClient.js b/packages/react-client/src/ReactFlightReplyClient.js
index 224af305d64b2..623a28760d4aa 100644
--- a/packages/react-client/src/ReactFlightReplyClient.js
+++ b/packages/react-client/src/ReactFlightReplyClient.js
@@ -7,12 +7,7 @@
  * @flow
  */
 
-import type {Thenable} from 'shared/ReactTypes';
-
-import {
-  knownServerReferences,
-  createServerReference,
-} from './ReactFlightServerReferenceRegistry';
+import type {Thenable, ReactCustomFormAction} from 'shared/ReactTypes';
 
 import {
   REACT_ELEMENT_TYPE,
@@ -28,6 +23,10 @@ import {
 } from 'shared/ReactSerializationErrors';
 
 import isArray from 'shared/isArray';
+import type {
+  FulfilledThenable,
+  RejectedThenable,
+} from '../../shared/ReactTypes';
 
 type ReactJSONValue =
   | string
@@ -39,6 +38,15 @@ type ReactJSONValue =
 
 export opaque type ServerReference<T> = T;
 
+export type CallServerCallback = <A, T>(id: any, args: A) => Promise<T>;
+
+export type ServerReferenceId = any;
+
+export const knownServerReferences: WeakMap<
+  Function,
+  {id: ServerReferenceId, bound: null | Thenable<Array<any>>},
+> = new WeakMap();
+
 // Serializable values
 export type ReactServerValue =
   // References are passed by their value
@@ -363,4 +371,104 @@ export function processReply(
   }
 }
 
-export {createServerReference};
+const boundCache: WeakMap<
+  {id: ServerReferenceId, bound: null | Thenable<Array<any>>},
+  Thenable<FormData>,
+> = new WeakMap();
+
+function encodeFormData(reference: any): Thenable<FormData> {
+  let resolve, reject;
+  // We need to have a handle on the thenable so that we can synchronously set
+  // its status from processReply, when it can complete synchronously.
+  const thenable: Thenable<FormData> = new Promise((res, rej) => {
+    resolve = res;
+    reject = rej;
+  });
+  processReply(
+    reference,
+    '',
+    (body: string | FormData) => {
+      if (typeof body === 'string') {
+        const data = new FormData();
+        data.append('0', body);
+        body = data;
+      }
+      const fulfilled: FulfilledThenable<FormData> = (thenable: any);
+      fulfilled.status = 'fulfilled';
+      fulfilled.value = body;
+      resolve(body);
+    },
+    e => {
+      const rejected: RejectedThenable<FormData> = (thenable: any);
+      rejected.status = 'rejected';
+      rejected.reason = e;
+      reject(e);
+    },
+  );
+  return thenable;
+}
+
+export function encodeFormAction(
+  this: any => Promise<any>,
+  identifierPrefix: string,
+): ReactCustomFormAction {
+  const reference = knownServerReferences.get(this);
+  if (!reference) {
+    throw new Error(
+      'Tried to encode a Server Action from a different instance than the encoder is from. ' +
+        'This is a bug in React.',
+    );
+  }
+  let data: null | FormData = null;
+  let name;
+  const boundPromise = reference.bound;
+  if (boundPromise !== null) {
+    let thenable = boundCache.get(reference);
+    if (!thenable) {
+      thenable = encodeFormData(reference);
+      boundCache.set(reference, thenable);
+    }
+    if (thenable.status === 'rejected') {
+      throw thenable.reason;
+    } else if (thenable.status !== 'fulfilled') {
+      throw thenable;
+    }
+    const encodedFormData = thenable.value;
+    // This is hacky but we need the identifier prefix to be added to
+    // all fields but the suspense cache would break since we might get
+    // a new identifier each time. So we just append it at the end instead.
+    const prefixedData = new FormData();
+    // $FlowFixMe[prop-missing]
+    encodedFormData.forEach((value: string | File, key: string) => {
+      prefixedData.append('$ACTION_' + identifierPrefix + ':' + key, value);
+    });
+    data = prefixedData;
+    // We encode the name of the prefix containing the data.
+    name = '$ACTION_REF_' + identifierPrefix;
+  } else {
+    // This is the simple case so we can just encode the ID.
+    name = '$ACTION_ID_' + reference.id;
+  }
+  return {
+    name: name,
+    method: 'POST',
+    encType: 'multipart/form-data',
+    data: data,
+  };
+}
+
+export function createServerReference<A: Iterable<any>, T>(
+  id: ServerReferenceId,
+  callServer: CallServerCallback,
+): (...A) => Promise<T> {
+  const proxy = function (): Promise<T> {
+    // $FlowFixMe[method-unbinding]
+    const args = Array.prototype.slice.call(arguments);
+    return callServer(id, args);
+  };
+  // Expose encoder for use by SSR.
+  // TODO: Only expose this in SSR builds and not the browser client.
+  proxy.$$FORM_ACTION = encodeFormAction;
+  knownServerReferences.set(proxy, {id: id, bound: null});
+  return proxy;
+}
diff --git a/packages/react-client/src/ReactFlightServerReferenceRegistry.js b/packages/react-client/src/ReactFlightServerReferenceRegistry.js
deleted file mode 100644
index 06ad06e9b3e46..0000000000000
--- a/packages/react-client/src/ReactFlightServerReferenceRegistry.js
+++ /dev/null
@@ -1,32 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- * @flow
- */
-
-import type {Thenable} from 'shared/ReactTypes';
-
-export type CallServerCallback = <A, T>(id: any, args: A) => Promise<T>;
-
-type ServerReferenceId = any;
-
-export const knownServerReferences: WeakMap<
-  Function,
-  {id: ServerReferenceId, bound: null | Thenable<Array<any>>},
-> = new WeakMap();
-
-export function createServerReference<A: Iterable<any>, T>(
-  id: ServerReferenceId,
-  callServer: CallServerCallback,
-): (...A) => Promise<T> {
-  const proxy = function (): Promise<T> {
-    // $FlowFixMe[method-unbinding]
-    const args = Array.prototype.slice.call(arguments);
-    return callServer(id, args);
-  };
-  knownServerReferences.set(proxy, {id: id, bound: null});
-  return proxy;
-}
diff --git a/packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js b/packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js
index b0c23a5c8dea3..353a534090b69 100644
--- a/packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js
+++ b/packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js
@@ -672,7 +672,7 @@ function makeFormFieldPrefix(responseState: ResponseState): string {
   // I'm just reusing this counter. It's not really the same namespace as "name".
   // It could just be its own counter.
   const id = responseState.nextSuspenseID++;
-  return responseState.idPrefix + '$ACTION:' + id + ':';
+  return responseState.idPrefix + id;
 }
 
 // Since this will likely be repeated a lot in the HTML, we use a more concise message
diff --git a/packages/react-server-dom-webpack/src/ReactFlightDOMServerBrowser.js b/packages/react-server-dom-webpack/src/ReactFlightDOMServerBrowser.js
index 777e4271e6e1e..24db03db06669 100644
--- a/packages/react-server-dom-webpack/src/ReactFlightDOMServerBrowser.js
+++ b/packages/react-server-dom-webpack/src/ReactFlightDOMServerBrowser.js
@@ -25,6 +25,8 @@ import {
   getRoot,
 } from 'react-server/src/ReactFlightReplyServer';
 
+import {decodeAction} from 'react-server/src/ReactFlightActionServer';
+
 type Options = {
   identifierPrefix?: string,
   signal?: AbortSignal,
@@ -87,4 +89,4 @@ function decodeReply<T>(
   return getRoot(response);
 }
 
-export {renderToReadableStream, decodeReply};
+export {renderToReadableStream, decodeReply, decodeAction};
diff --git a/packages/react-server-dom-webpack/src/ReactFlightDOMServerEdge.js b/packages/react-server-dom-webpack/src/ReactFlightDOMServerEdge.js
index 777e4271e6e1e..24db03db06669 100644
--- a/packages/react-server-dom-webpack/src/ReactFlightDOMServerEdge.js
+++ b/packages/react-server-dom-webpack/src/ReactFlightDOMServerEdge.js
@@ -25,6 +25,8 @@ import {
   getRoot,
 } from 'react-server/src/ReactFlightReplyServer';
 
+import {decodeAction} from 'react-server/src/ReactFlightActionServer';
+
 type Options = {
   identifierPrefix?: string,
   signal?: AbortSignal,
@@ -87,4 +89,4 @@ function decodeReply<T>(
   return getRoot(response);
 }
 
-export {renderToReadableStream, decodeReply};
+export {renderToReadableStream, decodeReply, decodeAction};
diff --git a/packages/react-server-dom-webpack/src/ReactFlightDOMServerNode.js b/packages/react-server-dom-webpack/src/ReactFlightDOMServerNode.js
index f23959b2f8bee..d98bf3baf1f9a 100644
--- a/packages/react-server-dom-webpack/src/ReactFlightDOMServerNode.js
+++ b/packages/react-server-dom-webpack/src/ReactFlightDOMServerNode.js
@@ -36,6 +36,8 @@ import {
   getRoot,
 } from 'react-server/src/ReactFlightReplyServer';
 
+import {decodeAction} from 'react-server/src/ReactFlightActionServer';
+
 function createDrainHandler(destination: Destination, request: Request) {
   return () => startFlowing(request, destination);
 }
@@ -148,4 +150,9 @@ function decodeReply<T>(
   return getRoot(response);
 }
 
-export {renderToPipeableStream, decodeReplyFromBusboy, decodeReply};
+export {
+  renderToPipeableStream,
+  decodeReplyFromBusboy,
+  decodeReply,
+  decodeAction,
+};
diff --git a/packages/react-server-dom-webpack/src/__tests__/ReactFlightDOMForm-test.js b/packages/react-server-dom-webpack/src/__tests__/ReactFlightDOMForm-test.js
new file mode 100644
index 0000000000000..51d208bce3eb4
--- /dev/null
+++ b/packages/react-server-dom-webpack/src/__tests__/ReactFlightDOMForm-test.js
@@ -0,0 +1,231 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @emails react-core
+ */
+
+'use strict';
+
+import {insertNodesAndExecuteScripts} from 'react-dom/src/test-utils/FizzTestUtils';
+
+// Polyfills for test environment
+global.ReadableStream =
+  require('web-streams-polyfill/ponyfill/es6').ReadableStream;
+global.TextEncoder = require('util').TextEncoder;
+global.TextDecoder = require('util').TextDecoder;
+
+let container;
+let serverExports;
+let webpackServerMap;
+let React;
+let ReactDOMServer;
+let ReactServerDOMServer;
+let ReactServerDOMClient;
+
+describe('ReactFlightDOMReply', () => {
+  beforeEach(() => {
+    jest.resetModules();
+    const WebpackMock = require('./utils/WebpackMock');
+    serverExports = WebpackMock.serverExports;
+    webpackServerMap = WebpackMock.webpackServerMap;
+    React = require('react');
+    ReactServerDOMServer = require('react-server-dom-webpack/server.browser');
+    ReactServerDOMClient = require('react-server-dom-webpack/client');
+    ReactDOMServer = require('react-dom/server.browser');
+    container = document.createElement('div');
+    document.body.appendChild(container);
+  });
+
+  afterEach(() => {
+    document.body.removeChild(container);
+  });
+
+  async function POST(formData) {
+    const boundAction = await ReactServerDOMServer.decodeAction(
+      formData,
+      webpackServerMap,
+    );
+    return boundAction();
+  }
+
+  function submit(submitter) {
+    const form = submitter.form || submitter;
+    if (!submitter.form) {
+      submitter = undefined;
+    }
+    const submitEvent = new Event('submit', {bubbles: true, cancelable: true});
+    submitEvent.submitter = submitter;
+    const returnValue = form.dispatchEvent(submitEvent);
+    if (!returnValue) {
+      return;
+    }
+    const action =
+      (submitter && submitter.getAttribute('formaction')) || form.action;
+    if (!/\s*javascript:/i.test(action)) {
+      const method = (submitter && submitter.formMethod) || form.method;
+      const encType = (submitter && submitter.formEnctype) || form.enctype;
+      if (method === 'post' && encType === 'multipart/form-data') {
+        let formData;
+        if (submitter) {
+          const temp = document.createElement('input');
+          temp.name = submitter.name;
+          temp.value = submitter.value;
+          submitter.parentNode.insertBefore(temp, submitter);
+          formData = new FormData(form);
+          temp.parentNode.removeChild(temp);
+        } else {
+          formData = new FormData(form);
+        }
+        return POST(formData);
+      }
+      throw new Error('Navigate to: ' + action);
+    }
+  }
+
+  async function readIntoContainer(stream) {
+    const reader = stream.getReader();
+    let result = '';
+    while (true) {
+      const {done, value} = await reader.read();
+      if (done) {
+        break;
+      }
+      result += Buffer.from(value).toString('utf8');
+    }
+    const temp = document.createElement('div');
+    temp.innerHTML = result;
+    insertNodesAndExecuteScripts(temp, container, null);
+  }
+
+  // @gate enableFormActions
+  it('can submit a passed server action without hydrating it', async () => {
+    let foo = null;
+
+    const serverAction = serverExports(function action(formData) {
+      foo = formData.get('foo');
+      return 'hello';
+    });
+    function App() {
+      return (
+        <form action={serverAction}>
+          <input type="text" name="foo" defaultValue="bar" />
+        </form>
+      );
+    }
+    const rscStream = ReactServerDOMServer.renderToReadableStream(<App />);
+    const response = ReactServerDOMClient.createFromReadableStream(rscStream);
+    const ssrStream = await ReactDOMServer.renderToReadableStream(response);
+    await readIntoContainer(ssrStream);
+
+    const form = container.firstChild;
+
+    expect(foo).toBe(null);
+
+    const result = await submit(form);
+
+    expect(result).toBe('hello');
+    expect(foo).toBe('bar');
+  });
+
+  // @gate enableFormActions
+  it('can submit an imported server action without hydrating it', async () => {
+    let foo = null;
+
+    const ServerModule = serverExports(function action(formData) {
+      foo = formData.get('foo');
+      return 'hi';
+    });
+    const serverAction = ReactServerDOMClient.createServerReference(
+      ServerModule.$$id,
+    );
+    function App() {
+      return (
+        <form action={serverAction}>
+          <input type="text" name="foo" defaultValue="bar" />
+        </form>
+      );
+    }
+
+    const ssrStream = await ReactDOMServer.renderToReadableStream(<App />);
+    await readIntoContainer(ssrStream);
+
+    const form = container.firstChild;
+
+    expect(foo).toBe(null);
+
+    const result = await submit(form);
+
+    expect(result).toBe('hi');
+
+    expect(foo).toBe('bar');
+  });
+
+  // @gate enableFormActions
+  it('can submit a complex closure server action without hydrating it', async () => {
+    let foo = null;
+
+    const serverAction = serverExports(function action(bound, formData) {
+      foo = formData.get('foo') + bound.complex;
+      return 'hello';
+    });
+    function App() {
+      return (
+        <form action={serverAction.bind(null, {complex: 'object'})}>
+          <input type="text" name="foo" defaultValue="bar" />
+        </form>
+      );
+    }
+    const rscStream = ReactServerDOMServer.renderToReadableStream(<App />);
+    const response = ReactServerDOMClient.createFromReadableStream(rscStream);
+    const ssrStream = await ReactDOMServer.renderToReadableStream(response);
+    await readIntoContainer(ssrStream);
+
+    const form = container.firstChild;
+
+    expect(foo).toBe(null);
+
+    const result = await submit(form);
+
+    expect(result).toBe('hello');
+    expect(foo).toBe('barobject');
+  });
+
+  // @gate enableFormActions
+  it('can submit a multiple complex closure server action without hydrating it', async () => {
+    let foo = null;
+
+    const serverAction = serverExports(function action(bound, formData) {
+      foo = formData.get('foo') + bound.complex;
+      return 'hello' + bound.complex;
+    });
+    function App() {
+      return (
+        <form action={serverAction.bind(null, {complex: 'a'})}>
+          <input type="text" name="foo" defaultValue="bar" />
+          <button formAction={serverAction.bind(null, {complex: 'b'})} />
+          <button formAction={serverAction.bind(null, {complex: 'c'})} />
+          <input
+            type="submit"
+            formAction={serverAction.bind(null, {complex: 'd'})}
+          />
+        </form>
+      );
+    }
+    const rscStream = ReactServerDOMServer.renderToReadableStream(<App />);
+    const response = ReactServerDOMClient.createFromReadableStream(rscStream);
+    const ssrStream = await ReactDOMServer.renderToReadableStream(response);
+    await readIntoContainer(ssrStream);
+
+    const form = container.firstChild;
+
+    expect(foo).toBe(null);
+
+    const result = await submit(form.getElementsByTagName('button')[1]);
+
+    expect(result).toBe('helloc');
+    expect(foo).toBe('barc');
+  });
+});
diff --git a/packages/react-server/src/ReactFlightActionServer.js b/packages/react-server/src/ReactFlightActionServer.js
new file mode 100644
index 0000000000000..ee735c2e8f9a2
--- /dev/null
+++ b/packages/react-server/src/ReactFlightActionServer.js
@@ -0,0 +1,110 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+
+import type {Thenable} from 'shared/ReactTypes';
+
+import type {
+  ServerManifest,
+  ClientReference as ServerReference,
+} from 'react-client/src/ReactFlightClientConfig';
+
+import {
+  resolveServerReference,
+  preloadModule,
+  requireModule,
+} from 'react-client/src/ReactFlightClientConfig';
+
+import {createResponse, close, getRoot} from './ReactFlightReplyServer';
+
+type ServerReferenceId = any;
+
+function bindArgs(fn: any, args: any) {
+  return fn.bind.apply(fn, [null].concat(args));
+}
+
+function loadServerReference<T>(
+  bundlerConfig: ServerManifest,
+  id: ServerReferenceId,
+  bound: null | Thenable<Array<any>>,
+): Promise<T> {
+  const serverReference: ServerReference<T> =
+    resolveServerReference<$FlowFixMe>(bundlerConfig, id);
+  // We expect most servers to not really need this because you'd just have all
+  // the relevant modules already loaded but it allows for lazy loading of code
+  // if needed.
+  const preloadPromise = preloadModule(serverReference);
+  if (bound) {
+    return Promise.all([(bound: any), preloadPromise]).then(
+      ([args]: Array<any>) => bindArgs(requireModule(serverReference), args),
+    );
+  } else if (preloadPromise) {
+    return Promise.resolve(preloadPromise).then(() =>
+      requireModule(serverReference),
+    );
+  } else {
+    // Synchronously available
+    return Promise.resolve(requireModule(serverReference));
+  }
+}
+
+export function decodeAction<T>(
+  body: FormData,
+  serverManifest: ServerManifest,
+): Promise<() => T> | null {
+  // We're going to create a new formData object that holds all the fields except
+  // the implementation details of the action data.
+  const formData = new FormData();
+
+  let action: Promise<(formData: FormData) => T> | null = null;
+
+  // $FlowFixMe[prop-missing]
+  body.forEach((value: string | File, key: string) => {
+    if (!key.startsWith('$ACTION_')) {
+      formData.append(key, value);
+      return;
+    }
+    // Later actions may override earlier actions if a button is used to override the default
+    // form action.
+    if (key.startsWith('$ACTION_REF_')) {
+      const formFieldPrefix = '$ACTION_' + key.slice(12) + ':';
+      // The data for this reference is encoded in multiple fields under this prefix.
+      const actionResponse = createResponse(
+        serverManifest,
+        formFieldPrefix,
+        body,
+      );
+      close(actionResponse);
+      const refPromise = getRoot<{
+        id: ServerReferenceId,
+        bound: null | Promise<Array<any>>,
+      }>(actionResponse);
+      // Force it to initialize
+      // $FlowFixMe
+      refPromise.then(() => {});
+      if (refPromise.status !== 'fulfilled') {
+        // $FlowFixMe
+        throw refPromise.reason;
+      }
+      const metaData = refPromise.value;
+      action = loadServerReference(serverManifest, metaData.id, metaData.bound);
+      return;
+    }
+    if (key.startsWith('$ACTION_ID_')) {
+      const id = key.slice(11);
+      action = loadServerReference(serverManifest, id, null);
+      return;
+    }
+  });
+
+  if (action === null) {
+    return null;
+  }
+  // Return the action with the remaining FormData bound to the first argument.
+  return action.then(fn => fn.bind(null, formData));
+}
diff --git a/scripts/error-codes/codes.json b/scripts/error-codes/codes.json
index e38f97f6c904d..b1ae802b33b56 100644
--- a/scripts/error-codes/codes.json
+++ b/scripts/error-codes/codes.json
@@ -465,5 +465,6 @@
   "477": "React Internal Error: processHintChunk is not implemented for Native-Relay. The fact that this method was called means there is a bug in React.",
   "478": "Thenable should have already resolved. This is a bug in React.",
   "479": "Cannot update optimistic state while rendering.",
-  "480": "File/Blob fields are not yet supported in progressive forms. It probably means you are closing over binary data or FormData in a Server Action."
+  "480": "File/Blob fields are not yet supported in progressive forms. It probably means you are closing over binary data or FormData in a Server Action.",
+  "481": "Tried to encode a Server Action from a different instance than the encoder is from. This is a bug in React."
 }