diff --git a/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.cpp b/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.cpp
index 9e07853..ea41361 100644
--- a/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.cpp
+++ b/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.cpp
@@ -110,7 +110,9 @@ CSteamNetworkConnectionP2P::CSteamNetworkConnectionP2P( CSteamNetworkingSockets
 	m_pCurrentTransportP2P = nullptr;
 	#ifdef STEAMNETWORKINGSOCKETS_ENABLE_SDR
 		m_pTransportP2PSDR = nullptr;
-		m_pTransportToSDRServer = nullptr;
+		#ifdef SDR_ENABLE_HOSTED_CLIENT
+			m_pTransportToSDRServer = nullptr;
+		#endif
 		#ifdef SDR_ENABLE_HOSTED_SERVER
 			m_pTransportFromSDRClient = nullptr;
 		#endif
@@ -813,11 +815,13 @@ void CSteamNetworkConnectionP2P::DestroyTransport()
 	#ifdef STEAMNETWORKINGSOCKETS_ENABLE_SDR
 		Assert( m_pTransportP2PSDR == nullptr ); // Should have been nuked above
 
-		if ( m_pTransportToSDRServer )
-		{
-			m_pTransportToSDRServer->TransportDestroySelfNow();
-			m_pTransportToSDRServer = nullptr;
-		}
+		#ifdef SDR_ENABLE_HOSTED_CLIENT
+			if ( m_pTransportToSDRServer )
+			{
+				m_pTransportToSDRServer->TransportDestroySelfNow();
+				m_pTransportToSDRServer = nullptr;
+			}
+		#endif
 
 		#ifdef SDR_ENABLE_HOSTED_SERVER
 			if ( m_pTransportFromSDRClient )
@@ -1690,12 +1694,17 @@ bool CSteamNetworkConnectionP2P::ProcessSignal( const CMsgSteamNetworkingP2PRend
 		// Check for SDR hosted server telling us to contact them via the special protocol
 		if ( msg.has_hosted_server_ticket() )
 		{
-			if ( !IsSDRHostedServerClient() )
-			{
-				SpewMsgGroup( LogLevel_P2PRendezvous(), "[%s] Peer sent hosted_server_ticket.  Switching to SDR client transport\n", GetDescription() );
-				if ( !BSelectTransportToSDRServerFromSignal( msg ) )
-					return false;
-			}
+			#ifdef SDR_ENABLE_HOSTED_CLIENT
+				if ( !IsSDRHostedServerClient() )
+				{
+					SpewMsgGroup( LogLevel_P2PRendezvous(), "[%s] Peer sent hosted_server_ticket.  Switching to SDR client transport\n", GetDescription() );
+					if ( !BSelectTransportToSDRServerFromSignal( msg ) )
+						return false;
+				}
+			#else
+				ConnectionState_ProblemDetectedLocally( k_ESteamNetConnectionEnd_Misc_P2P_Rendezvous, "Peer is a hosted dedicated server.  Not supported." );
+				return false;
+			#endif
 		}
 
 		// Go ahead and process the SDR P2P routes, if they are sending them
@@ -1910,7 +1919,7 @@ ESteamNetConnectionEnd CSteamNetworkConnectionP2P::CheckRemoteCert( const CertAu
 
 	// If ticket was bound to a data center, then make sure the cert chain authorizes
 	// them to send us there.
-	#ifdef STEAMNETWORKINGSOCKETS_ENABLE_SDR
+	#ifdef SDR_ENABLE_HOSTED_CLIENT
 		if ( m_pTransportToSDRServer )
 		{
 			SteamNetworkingPOPID popIDTicket = m_pTransportToSDRServer->m_authTicket.m_ticket.m_routing.GetPopID();
diff --git a/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.h b/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.h
index 7efa064..fc36946 100644
--- a/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.h
+++ b/src/steamnetworkingsockets/clientlib/steamnetworkingsockets_p2p.h
@@ -267,14 +267,16 @@ public:
 		// Peer to peer, over SDR
 		CConnectionTransportP2PSDR *m_pTransportP2PSDR;
 		CMsgSteamNetworkingP2PSDRRoutingSummary m_msgSDRRoutingSummary;
+	#endif
 
-		// Client connecting to hosted dedicated server over SDR.  These are not really
-		// "Peer to peer" connections.  In a previous iteration of the code these were
-		// a totally separate connection class, because we always knew when initiating
-		// the connection that it was going to be this type.  However, now these connections
-		// may begin their life as an ordinary P2P connection, and only discover from a signal
-		// from the peer that it is a server in a hosted data center.  Then they will switch to
-		// use the special-case optimized transport.
+	// Client connecting to hosted dedicated server over SDR.  These are not really
+	// "Peer to peer" connections.  In a previous iteration of the code these were
+	// a totally separate connection class, because we always knew when initiating
+	// the connection that it was going to be this type.  However, now these connections
+	// may begin their life as an ordinary P2P connection, and only discover from a signal
+	// from the peer that it is a server in a hosted data center.  Then they will switch to
+	// use the special-case optimized transport.
+	#ifdef SDR_ENABLE_HOSTED_CLIENT
 		CConnectionTransportToSDRServer *m_pTransportToSDRServer;
 		bool BInitConnectToSDRServer( const SteamNetworkingIdentity &identityTarget, int nRemoteVirtualPort, int nOptions, const SteamNetworkingConfigValue_t *pOptions, SteamNetworkingErrMsg &errMsg );
 		bool BSelectTransportToSDRServerFromSignal( const CMsgSteamNetworkingP2PRendezvous &msg );
@@ -288,25 +290,23 @@ public:
 			}
 			return false;
 		}
-
-		// We are the server in special hosted data center
-		#ifdef SDR_ENABLE_HOSTED_SERVER
-			CConnectionTransportFromSDRClient *m_pTransportFromSDRClient;
-			inline bool IsSDRHostedServer() const
-			{
-				if ( m_pTransportFromSDRClient )
-				{
-					Assert( m_vecAvailableTransports.empty() );
-					return true;
-				}
-				return false;
-			}
-		#else
-			inline bool IsSDRHostedServer() const { return false; }
-		#endif
-
 	#else
 		inline bool IsSDRHostedServerClient() const { return false; }
+	#endif
+
+	// We are the server in special hosted data center
+	#ifdef SDR_ENABLE_HOSTED_SERVER
+		CConnectionTransportFromSDRClient *m_pTransportFromSDRClient;
+		inline bool IsSDRHostedServer() const
+		{
+			if ( m_pTransportFromSDRClient )
+			{
+				Assert( m_vecAvailableTransports.empty() );
+				return true;
+			}
+			return false;
+		}
+	#else
 		inline bool IsSDRHostedServer() const { return false; }
 	#endif
 
diff --git a/src/steamnetworkingsockets/steamnetworkingsockets_internal.h b/src/steamnetworkingsockets/steamnetworkingsockets_internal.h
index 31b612e..97e6008 100644
--- a/src/steamnetworkingsockets/steamnetworkingsockets_internal.h
+++ b/src/steamnetworkingsockets/steamnetworkingsockets_internal.h
@@ -85,10 +85,10 @@
 	#define STEAMNETWORKINGSOCKETS_CAN_REQUEST_CERT
 #endif
 
-// Always #define STEAMNETWORKINGSOCKETS_ENABLE_ICE, except in the opensource build.
-// There, it must go on the command line
+// Always #define STEAMNETWORKINGSOCKETS_ENABLE_ICE in a few places.
+// You can also define it on the command line
 #ifndef STEAMNETWORKINGSOCKETS_ENABLE_ICE
-	#ifndef STEAMNETWORKINGSOCKETS_OPENSOURCE
+	#if defined( STEAMNETWORKINGSOCKETS_STEAMCLIENT ) || defined( STEAMNETWORKINGSOCKETS_STREAMINGCLIENT )
 		#define STEAMNETWORKINGSOCKETS_ENABLE_ICE
 	#endif
 #endif