diff --git a/examples/her/her_dqn_gridworld.py b/examples/her/her_dqn_gridworld.py
new file mode 100644
index 000000000..eb56e9adc
--- /dev/null
+++ b/examples/her/her_dqn_gridworld.py
@@ -0,0 +1,73 @@
+"""
+This should results in an average return of -20 by the end of training.
+
+Usually hits -30 around epoch 50.
+Note that one epoch = 5k steps, so 200 epochs = 1 million steps.
+"""
+import gym
+
+import rlkit.torch.pytorch_util as ptu
+from rlkit.data_management.obs_dict_replay_buffer import ObsDictRelabelingBuffer
+from rlkit.exploration_strategies.base import (
+    PolicyWrappedWithExplorationStrategy
+)
+from rlkit.exploration_strategies.gaussian_and_epsilon_strategy import (
+    GaussianAndEpislonStrategy
+)
+from rlkit.launchers.launcher_util import setup_logger
+from rlkit.torch.her.her import HerDQN
+from rlkit.torch.networks import FlattenMlp, TanhMlpPolicy
+import multiworld.envs.gridworlds
+
+
+def experiment(variant):
+    env = gym.make('GoalGridworld-v0')
+
+    obs_dim = env.observation_space.spaces['observation'].low.size
+    goal_dim = env.observation_space.spaces['desired_goal'].low.size
+    action_dim = env.action_space.n
+    qf1 = FlattenMlp(
+        input_size=obs_dim + goal_dim,
+        output_size=action_dim,
+        hidden_sizes=[400, 300],
+    )
+
+
+    replay_buffer = ObsDictRelabelingBuffer(
+        env=env,
+        **variant['replay_buffer_kwargs']
+    )
+    algorithm = HerDQN(
+        her_kwargs=dict(
+            observation_key='observation',
+            desired_goal_key='desired_goal'
+        ),
+        dqn_kwargs = dict(
+            env=env,
+            qf=qf1,
+        ),
+        replay_buffer=replay_buffer,
+        **variant['algo_kwargs']
+    )
+    algorithm.to(ptu.device)
+    algorithm.train()
+
+
+if __name__ == "__main__":
+    variant = dict(
+        algo_kwargs=dict(
+            num_epochs=100,
+            num_steps_per_epoch=1000,
+            num_steps_per_eval=1000,
+            max_path_length=50,
+            batch_size=128,
+            discount=0.99,
+        ),
+        replay_buffer_kwargs=dict(
+            max_size=100000,
+            fraction_goals_rollout_goals=0.2,  # equal to k = 4 in HER paper
+            fraction_goals_env_goals=0.0,
+        ),
+    )
+    setup_logger('her-dqn-gridworld-experiment', variant=variant)
+    experiment(variant)
diff --git a/rlkit/data_management/obs_dict_replay_buffer.py b/rlkit/data_management/obs_dict_replay_buffer.py
index f7a69763c..bae897d03 100644
--- a/rlkit/data_management/obs_dict_replay_buffer.py
+++ b/rlkit/data_management/obs_dict_replay_buffer.py
@@ -66,8 +66,10 @@ def __init__(
         self.observation_key = observation_key
         self.desired_goal_key = desired_goal_key
         self.achieved_goal_key = achieved_goal_key
-
-        self._action_dim = env.action_space.low.size
+        if isinstance(self.env.action_space, Discrete):
+            self._action_dim = env.action_space.n
+        else:
+            self._action_dim = env.action_space.low.size
         self._actions = np.zeros((max_size, self._action_dim))
         # self._terminals[i] = a terminal was received at time i
         self._terminals = np.zeros((max_size, 1), dtype='uint8')
@@ -93,8 +95,6 @@ def __init__(
         # Then self._next_obs[j] is a valid next observation for observation i
         self._idx_to_future_obs_idx = [None] * max_size
 
-        if isinstance(self.env.action_space, Discrete):
-            raise NotImplementedError("TODO. See issue 28.")
 
     def add_sample(self, observation, action, reward, terminal,
                    next_observation, **kwargs):
@@ -115,6 +115,8 @@ def add_path(self, path):
         path_len = len(rewards)
 
         actions = flatten_n(actions)
+        if isinstance(self.env.action_space, Discrete):
+            actions = np.eye(self._action_dim)[actions].reshape((-1, self._action_dim))
         obs = flatten_dict(obs, self.ob_keys_to_save + self.internal_keys)
         next_obs = flatten_dict(next_obs,
                                 self.ob_keys_to_save + self.internal_keys)
diff --git a/rlkit/samplers/rollout_functions.py b/rlkit/samplers/rollout_functions.py
index 2701efcef..217fe443b 100644
--- a/rlkit/samplers/rollout_functions.py
+++ b/rlkit/samplers/rollout_functions.py
@@ -68,7 +68,6 @@ def multitask_rollout(
         if d:
             break
         o = next_o
-    full_observations.append(o)
     actions = np.array(actions)
     if len(actions.shape) == 1:
         actions = np.expand_dims(actions, 1)
diff --git a/rlkit/torch/her/her.py b/rlkit/torch/her/her.py
index fa5f92c3e..e7518037f 100644
--- a/rlkit/torch/her/her.py
+++ b/rlkit/torch/her/her.py
@@ -9,6 +9,7 @@
 from rlkit.torch.sac.sac import SoftActorCritic
 from rlkit.torch.sac.twin_sac import TwinSAC
 from rlkit.torch.td3.td3 import TD3
+from rlkit.torch.dqn.dqn import DQN
 from rlkit.torch.torch_rl_algorithm import TorchRLAlgorithm
 
 
@@ -194,3 +195,19 @@ def __init__(
         ) or isinstance(
             self.replay_buffer, ObsDictRelabelingBuffer
         )
+
+class HerDQN(HER, DQN):
+    def __init__(
+            self,
+            *args,
+            her_kwargs,
+            dqn_kwargs,
+            **kwargs
+    ):
+        HER.__init__(self, **her_kwargs)
+        DQN.__init__(self, *args, **kwargs, **dqn_kwargs)
+        assert isinstance(
+            self.replay_buffer, RelabelingReplayBuffer
+        ) or isinstance(
+            self.replay_buffer, ObsDictRelabelingBuffer
+        )