diff --git a/src/core/netplay.cpp b/src/core/netplay.cpp
index fe5291861..48e0dc0f2 100644
--- a/src/core/netplay.cpp
+++ b/src/core/netplay.cpp
@@ -159,6 +159,10 @@ static std::bitset<MAX_PLAYERS> s_reset_players;
 static Common::Timer s_reset_start_time;
 static Common::Timer s_last_host_connection_attempt;
 
+// Spectators
+static std::array<Peer, MAX_SPECTATORS> s_spectators;
+static bool s_local_spectating;
+
 /// GGPO
 static std::string s_local_nickname;
 static std::string s_local_session_password;
diff --git a/src/core/netplay.h b/src/core/netplay.h
index 082b3e60b..36d560338 100644
--- a/src/core/netplay.h
+++ b/src/core/netplay.h
@@ -10,6 +10,9 @@ enum : s32
   // Maximum number of emulated controllers.
   MAX_PLAYERS = 2,
 
+  // Maximum number of spectators allowed to watch the session.
+  MAX_SPECTATORS = 4,
+
   // Maximum netplay prediction frames
   MAX_ROLLBACK_FRAMES = 8,
 
diff --git a/src/duckstation-qt/joinnetplaysessiondialog.ui b/src/duckstation-qt/joinnetplaysessiondialog.ui
index 603884899..0a2e8d97e 100644
--- a/src/duckstation-qt/joinnetplaysessiondialog.ui
+++ b/src/duckstation-qt/joinnetplaysessiondialog.ui
@@ -10,7 +10,7 @@
     <x>0</x>
     <y>0</y>
     <width>480</width>
-    <height>220</height>
+    <height>226</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -146,11 +146,28 @@
     </layout>
    </item>
    <item>
-    <widget class="QDialogButtonBox" name="buttonBox">
-     <property name="standardButtons">
-      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
-     </property>
-    </widget>
+    <layout class="QHBoxLayout" name="horizontalLayout_2">
+     <item>
+      <widget class="QCheckBox" name="spectating">
+       <property name="layoutDirection">
+        <enum>Qt::LeftToRight</enum>
+       </property>
+       <property name="text">
+        <string>Enable Spectator Mode</string>
+       </property>
+       <property name="checkable">
+        <bool>true</bool>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QDialogButtonBox" name="buttonBox">
+       <property name="standardButtons">
+        <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
+       </property>
+      </widget>
+     </item>
+    </layout>
    </item>
   </layout>
  </widget>