diff --git a/lib/src/joiner.dart b/lib/src/joiner.dart
index f8f0a70..649119c 100644
--- a/lib/src/joiner.dart
+++ b/lib/src/joiner.dart
@@ -6,7 +6,12 @@ import "package:wampproto/src/types.dart";
 
 final clientRoles = <String, Map<String, Map>>{
   "caller": {"features": {}},
-  "callee": {"features": {}},
+  "callee": {
+    "features": {
+      "progressive_call_results": true,
+      "call_canceling": true,
+    },
+  },
   "publisher": {"features": {}},
   "subscriber": {"features": {}},
 };
diff --git a/lib/src/session.dart b/lib/src/session.dart
index df0ff9f..eff19d9 100644
--- a/lib/src/session.dart
+++ b/lib/src/session.dart
@@ -1,5 +1,6 @@
 import "package:wampproto/messages.dart";
 import "package:wampproto/serializers.dart";
+import "package:wampproto/src/dealer.dart";
 import "package:wampproto/src/exception.dart";
 
 class WAMPSession {
@@ -37,7 +38,10 @@ class WAMPSession {
       if (!_invocationRequests.containsKey(msg.requestID)) {
         throw ArgumentError("cannot yield for unknown invocation request");
       }
-      _invocationRequests.remove(msg.requestID);
+      bool progress = msg.options[optionProgress] ?? false;
+      if (!progress) {
+        _invocationRequests.remove(msg.requestID);
+      }
 
       return _serializer.serialize(msg);
     } else if (msg is Publish) {
@@ -78,8 +82,10 @@ class WAMPSession {
       if (!_callRequests.containsKey(msg.requestID)) {
         throw ProtocolError("received RESULT for invalid request ID ${msg.requestID}");
       }
-      _callRequests.remove(msg.requestID);
-
+      bool progress = msg.details["progress"] ?? false;
+      if (!progress) {
+        _callRequests.remove(msg.requestID);
+      }
       return msg;
     } else if (msg is Registered) {
       if (!_registerRequests.containsKey(msg.requestID)) {