diff --git a/apps/threads.lua b/apps/threads.lua
index 4ff7d6e..a9107fa 100644
--- a/apps/threads.lua
+++ b/apps/threads.lua
@@ -94,6 +94,7 @@ app:get("thread", "/:slug", function(self)
     "WHERE posts.thread_id = ? ORDER BY posts.created_at ASC LIMIT ? OFFSET ?")
   local posts = db.query(query, thread.id, POSTS_PER_PAGE, (self.page - 1) * POSTS_PER_PAGE)
   self.topic = Topics:find(thread.topic_id)
+  self.other_topics = db.query("SELECT topics.id, topics.name FROM topics")
   self.me = util.get_logged_in_user_or_transient(self)
   self.posts = posts
 
@@ -169,4 +170,40 @@ app:post("thread_sticky", "/:slug/sticky", function(self)
   return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
 end)
 
+app:post("thread_move", "/:slug/move", function(self)
+  local user = util.get_logged_in_user(self)
+  if not user then
+    return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+  end
+  
+  if not user:is_mod() then
+    return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+  end
+  
+  if not self.params.new_topic_id then
+    util.inject_err_infobox(self, "Thread already in this topic.")
+    return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+  end
+  
+  local new_topic = Topics:find({id = self.params.new_topic_id})
+  if not new_topic then
+    return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+  end
+  local thread = Threads:find({slug = self.params.slug})
+  if not thread then
+    return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+  end
+  if new_topic.id == thread.topic_id then
+    util.inject_err_infobox(self, "Thread already in this topic.")
+    return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+  end
+  
+  local old_topic = Topics:find({id = thread.topic_id})
+  
+  thread:update({topic_id = new_topic.id})
+  util.inject_infobox(self, ("Thread moved from \"%s\" to \"%s\"."):format(old_topic.name, new_topic.name))
+  
+  return {redirect_to = self:url_for("thread", {slug = self.params.slug})}
+end)
+
 return app
diff --git a/views/threads/thread.etlua b/views/threads/thread.etlua
index 6bddbb0..fa8b374 100644
--- a/views/threads/thread.etlua
+++ b/views/threads/thread.etlua
@@ -25,6 +25,15 @@
           <input type=hidden value="<%= not is_stickied %>" name="target_op">
           <input class="warn" type="submit" value="<%= is_stickied and "Unsticky thread" or "Sticky thread" %>">
         </form>
+        <form class="modform" action="<%= url_for("thread_move", {slug = thread.slug}) %>" method="post">
+          <label for="new_topic_id">Move to topic:</label>
+          <select style="width:200px;" id="new_topic_id" name="new_topic_id" autocomplete="off">
+            <% for _, topic in ipairs(other_topics) do %>
+              <option value="<%= topic.id %>" <%- thread.topic_id == topic.id and "selected disabled" or "" %>><%= topic.name %></option>
+            <% end %>
+          </select>
+          <input class="warn" type="submit" value="Move thread">
+        </form>
       <% end %>
     </div>
     <% end %>