diff --git a/clients/c/cosmopolite.c b/clients/c/cosmopolite.c
index daf47ee..e210727 100644
--- a/clients/c/cosmopolite.c
+++ b/clients/c/cosmopolite.c
@@ -43,6 +43,20 @@ static json_t *cosmo_find_subscription(cosmo *instance, json_t *subject) {
   return NULL;
 }
 
+static void cosmo_send_command_locked(cosmo *instance, json_t *command) {
+  json_array_append_new(instance->command_queue, command);
+  instance->next_delay_ms = 0;
+}
+
+// Takes ownership of command.
+static void cosmo_send_command(cosmo *instance, json_t *command) {
+  assert(command);
+  assert(!pthread_mutex_lock(&instance->lock));
+  cosmo_send_command_locked(instance, command);
+  assert(!pthread_cond_signal(&instance->cond));
+  assert(!pthread_mutex_unlock(&instance->lock));
+}
+
 static size_t cosmo_read_callback(void *ptr, size_t size, size_t nmemb, void *userp) {
   cosmo_transfer *transfer = userp;
   size_t to_write = min(transfer->send_buf_len, size * nmemb);
@@ -326,8 +340,7 @@ static json_t *cosmo_send_rpc(cosmo *instance, json_t *commands, json_t *ack) {
           }
         }
 
-        json_array_append_new(instance->command_queue, cosmo_command("subscribe", arguments));
-        instance->next_delay_ms = 0;
+        cosmo_send_command_locked(instance, cosmo_command("subscribe", arguments));
       }
       assert(!pthread_mutex_unlock(&instance->lock));
     }
@@ -410,16 +423,6 @@ static void *cosmo_thread_main(void *arg) {
   return NULL;
 }
 
-// Takes ownership of command.
-static void cosmo_send_command(cosmo *instance, json_t *command) {
-  assert(command);
-  assert(!pthread_mutex_lock(&instance->lock));
-  json_array_append_new(instance->command_queue, command);
-  instance->next_delay_ms = 0;
-  assert(!pthread_cond_signal(&instance->cond));
-  assert(!pthread_mutex_unlock(&instance->lock));
-}
-
 
 // Public interface below
 
@@ -444,26 +447,40 @@ json_t *cosmo_subject(const char *name, const char *readable_only_by, const char
   return ret;
 }
 
-void cosmo_subscribe(cosmo *instance, json_t *subject, const json_int_t messages, const json_int_t last_id) {
-  assert(!pthread_mutex_lock(&instance->lock));
-  json_t *subscription = cosmo_find_subscription(instance, subject);
-  if (!subscription) {
-    subscription = json_pack("{sOs[]si}", "subject", subject, "messages", "state", SUBSCRIPTION_PENDING);
-    json_array_append_new(instance->subscriptions, subscription);
+void cosmo_subscribe(cosmo *instance, json_t *subjects, const json_int_t messages, const json_int_t last_id) {
+  if (json_is_array(subjects)) {
+    json_incref(subjects);
+  } else {
+    subjects = json_pack("[O]", subjects);
+    assert(subjects);
   }
 
-  json_t *arguments = json_pack("{sO}", "subject", subject);
-  if (messages) {
-    json_object_set_new(arguments, "messages", json_integer(messages));
-    json_object_set_new(subscription, "num_messages", json_integer(messages));
-  }
-  if (last_id) {
-    json_object_set_new(arguments, "last_id", json_integer(last_id));
-    json_object_set_new(subscription, "last_id", json_integer(last_id));
+  assert(!pthread_mutex_lock(&instance->lock));
+  size_t i;
+  json_t *subject;
+  json_array_foreach(subjects, i, subject) {
+    json_t *subscription = cosmo_find_subscription(instance, subject);
+    if (!subscription) {
+      subscription = json_pack("{sOs[]si}", "subject", subject, "messages", "state", SUBSCRIPTION_PENDING);
+      json_array_append_new(instance->subscriptions, subscription);
+    }
+
+    json_t *arguments = json_pack("{sO}", "subject", subject);
+    if (messages) {
+      json_object_set_new(arguments, "messages", json_integer(messages));
+      json_object_set_new(subscription, "num_messages", json_integer(messages));
+    }
+    if (last_id) {
+      json_object_set_new(arguments, "last_id", json_integer(last_id));
+      json_object_set_new(subscription, "last_id", json_integer(last_id));
+    }
+    cosmo_send_command_locked(instance, cosmo_command("subscribe", arguments));
   }
   assert(!pthread_mutex_unlock(&instance->lock));
 
-  cosmo_send_command(instance, cosmo_command("subscribe", arguments));
+  pthread_cond_signal(&instance->cond);
+
+  json_decref(subjects);
 }
 
 void cosmo_unsubscribe(cosmo *instance, json_t *subject) {
diff --git a/clients/c/cosmopolite.h b/clients/c/cosmopolite.h
index 96d6ec0..4526e9f 100644
--- a/clients/c/cosmopolite.h
+++ b/clients/c/cosmopolite.h
@@ -28,7 +28,7 @@ void cosmo_shutdown(cosmo *instance);
 const char *cosmo_current_profile(cosmo *instance);
 
 json_t *cosmo_subject(const char *name, const char *readable_only_by, const char *writeable_only_by);
-void cosmo_subscribe(cosmo *instance, json_t *subject, const json_int_t messages, const json_int_t last_id);
+void cosmo_subscribe(cosmo *instance, json_t *subjects, const json_int_t messages, const json_int_t last_id);
 void cosmo_unsubscribe(cosmo *instance, json_t *subject);
 void cosmo_send_message(cosmo *instance, json_t *subject, json_t *message);
 
diff --git a/clients/c/test.c b/clients/c/test.c
index 70b5936..2b5eeac 100644
--- a/clients/c/test.c
+++ b/clients/c/test.c
@@ -226,12 +226,39 @@ bool test_resubscribe(test_state *state) {
   return true;
 }
 
+bool test_bulk_subscribe(test_state *state) {
+  cosmo *client = create_client(state);
+
+  json_t *subject1 = random_subject(NULL, NULL);
+  json_t *subject2 = random_subject(NULL, NULL);
+  json_t *subjects = json_pack("[oo]", subject1, subject2);
+  cosmo_subscribe(client, subjects, -1, 0);
+
+  json_t *message_out = random_message();
+  cosmo_send_message(client, subject1, message_out);
+  const json_t *message_in = wait_for_message(state);
+  assert(json_equal(message_out, json_object_get(message_in, "message")));
+  json_decref(message_out);
+
+  message_out = random_message();
+  cosmo_send_message(client, subject2, message_out);
+  message_in = wait_for_message(state);
+  assert(json_equal(message_out, json_object_get(message_in, "message")));
+  json_decref(message_out);
+
+  json_decref(subjects);
+
+  cosmo_shutdown(client);
+  return true;
+}
+
 int main(int argc, char *argv[]) {
   RUN_TEST(test_create_shutdown);
   RUN_TEST(test_connect_logout_fires);
   RUN_TEST(test_message_round_trip);
   RUN_TEST(test_resubscribe);
   RUN_TEST(test_reconnect);
+  RUN_TEST(test_bulk_subscribe);
 
   return 0;
 }