diff --git a/src/main/java/com/evolveum/polygon/connector/grouper/rest/AbstractGroupProcessor.java b/src/main/java/com/evolveum/polygon/connector/grouper/rest/AbstractGroupProcessor.java
index 991cb7c..410b235 100644
--- a/src/main/java/com/evolveum/polygon/connector/grouper/rest/AbstractGroupProcessor.java
+++ b/src/main/java/com/evolveum/polygon/connector/grouper/rest/AbstractGroupProcessor.java
@@ -58,8 +58,8 @@ void read(Filter filter, ResultsHandler handler, OperationOptions options) {
 		}
 	}
 
-	void getGroupByUuid(String uuid, ResultsHandler handler, OperationOptions options) {
-		getGroupByUuid(uuid, handler);
+	boolean getGroupByUuid(String uuid, ResultsHandler handler, OperationOptions options) {
+		return getGroupByUuid(uuid, handler);
 	}
 
 	void getGroupByName(String name, ResultsHandler handler, OperationOptions options) {
@@ -68,7 +68,7 @@ void getGroupByName(String name, ResultsHandler handler, OperationOptions option
 
 	abstract void getAllGroups(ResultsHandler handler, OperationOptions options);
 
-	void executeFindGroupsResponse(HttpPost request, JSONObject body, ResultsHandler handler) {
+	boolean executeFindGroupsResponse(HttpPost request, JSONObject body, ResultsHandler handler) {
 		System.out.println("Request = " + body.toString());
 		JSONObject response = processor.callRequest(request, body, true, CONTENT_TYPE_JSON);
 		System.out.println("Got response: " + response);
@@ -77,10 +77,11 @@ void executeFindGroupsResponse(HttpPost request, JSONObject body, ResultsHandler
 		if (groups != null) {
 			for (Object group : groups) {
 				if (!handleGroupJsonObject(group, handler)) {
-					return;
+					return false;
 				}
 			}
 		}
+		return true;
 	}
 
 	void executeFindGroupsAsMembersResponse(HttpPost request, JSONObject body, ResultsHandler handler) {
@@ -111,7 +112,7 @@ void getGroupByName(String groupName, ResultsHandler handler) {
 		}
 	}
 
-	void getGroupByUuid(String groupUuid, ResultsHandler handler) {
+	boolean getGroupByUuid(String groupUuid, ResultsHandler handler) {
 		URIBuilder uriBuilder = processor.getURIBuilder()
 				.setPath(URI_BASE_PATH + PATH_GROUPS);
 		try {
@@ -120,7 +121,7 @@ void getGroupByUuid(String groupUuid, ResultsHandler handler) {
 					.put("WsRestFindGroupsRequest", new JSONObject()
 							.put("wsGroupLookups", new JSONObject[] { new JSONObject()
 									.put("uuid", groupUuid) }));
-			executeFindGroupsResponse(request, body, handler);
+			return executeFindGroupsResponse(request, body, handler);
 		} catch (RuntimeException | URISyntaxException e) {
 			throw processor.processException(e, uriBuilder, "Get all groups");
 		}
diff --git a/src/main/java/com/evolveum/polygon/connector/grouper/rest/PlainGroupProcessor.java b/src/main/java/com/evolveum/polygon/connector/grouper/rest/PlainGroupProcessor.java
index 4443ff0..e4d5d44 100644
--- a/src/main/java/com/evolveum/polygon/connector/grouper/rest/PlainGroupProcessor.java
+++ b/src/main/java/com/evolveum/polygon/connector/grouper/rest/PlainGroupProcessor.java
@@ -55,11 +55,22 @@ ObjectClassInfoBuilder buildSchema() {
 		return builder;
 	}
 
-	protected void getAllGroups(ResultsHandler handler, OperationOptions options) {
+	protected void getAllGroups(final ResultsHandler handler, final OperationOptions options) {
 		boolean isGetMembers = isGetMembers(options);
-		if (isGetMembers) {
-			throw new IllegalArgumentException("Cannot get members when retrieving all groups");
+		if (!isGetMembers) {
+			getAllGroupsNoMembers(handler);
+		} else {
+			ResultsHandler localHandler = new ResultsHandler() {
+				@Override
+				public boolean handle(ConnectorObject connectorObject) {
+					return getGroupByUuid(connectorObject.getUid().getUidValue(), handler, options);
+				}
+			};
+			getAllGroupsNoMembers(localHandler);
 		}
+	}
+
+	private void getAllGroupsNoMembers(ResultsHandler handler) {
 		URIBuilder uriBuilder = processor.getURIBuilder()
 				.setPath(URI_BASE_PATH + PATH_GROUPS);
 		try {
@@ -77,9 +88,9 @@ protected void getAllGroups(ResultsHandler handler, OperationOptions options) {
 	}
 
 	@Override
-	void getGroupByUuid(String uuid, ResultsHandler handler, OperationOptions options) {
+	boolean getGroupByUuid(String uuid, ResultsHandler handler, OperationOptions options) {
 		if (!isGetMembers(options)) {
-			getGroupByUuid(uuid, handler);
+			return getGroupByUuid(uuid, handler);
 		} else {
 			URIBuilder uriBuilder = processor.getURIBuilder()
 					.setPath(URI_BASE_PATH + PATH_GROUPS);
@@ -90,7 +101,7 @@ void getGroupByUuid(String uuid, ResultsHandler handler, OperationOptions option
 								.put("wsGroupLookups", new JSONObject[] { new JSONObject()
 										.put("uuid", uuid) })
 								.put("includeSubjectDetail", true));
-				executeGetGroupWithMembersResponse(request, body, handler);
+				return executeGetGroupWithMembersResponse(request, body, handler);
 			} catch (RuntimeException | URISyntaxException e) {
 				throw processor.processException(e, uriBuilder, "Get all groups");
 			}
@@ -119,7 +130,7 @@ void getGroupByName(String name, ResultsHandler handler, OperationOptions option
 		}
 	}
 
-	private void executeGetGroupWithMembersResponse(HttpPost request, JSONObject body, ResultsHandler handler) {
+	private boolean executeGetGroupWithMembersResponse(HttpPost request, JSONObject body, ResultsHandler handler) {
 		System.out.println("Request = " + body.toString());
 		JSONObject response = processor.callRequest(request, body, true, CONTENT_TYPE_JSON);
 		System.out.println("Got response: " + response);
@@ -136,23 +147,25 @@ private void executeGetGroupWithMembersResponse(HttpPost request, JSONObject bod
 		builder.addAttribute(ATTR_EXTENSION, extension);
 
 		List<String> subjects = new ArrayList<>();
-		JSONArray members = processor.getArray(response, WS_GET_MEMBERS_RESULTS, RESULTS, WS_SUBJECTS);
-		for (Object memberObject : members) {
-			JSONObject member = (JSONObject) memberObject;
-			String sourceId = processor.getStringOrNull(member, "sourceId");
-			if (sourceId == null || !sourceId.equals(getConfiguration().getSubjectSource())) {
-				LOG.info("Skipping non-person member (source={0})", sourceId);
-				continue;
-			}
-			String subjectId = processor.getStringOrNull(member, "id");
-			if (subjectId != null) {
-				subjects.add(subjectId);
-			} else {
-				LOG.info("Skipping unnamed member (source={0})", member);
+		JSONArray members = processor.getArray(response, false, WS_GET_MEMBERS_RESULTS, RESULTS, WS_SUBJECTS);
+		if (members != null) {
+			for (Object memberObject : members) {
+				JSONObject member = (JSONObject) memberObject;
+				String sourceId = processor.getStringOrNull(member, "sourceId");
+				if (sourceId == null || !sourceId.equals(getConfiguration().getSubjectSource())) {
+					LOG.info("Skipping non-person member (source={0})", sourceId);
+					continue;
+				}
+				String subjectId = processor.getStringOrNull(member, "id");
+				if (subjectId != null) {
+					subjects.add(subjectId);
+				} else {
+					LOG.info("Skipping unnamed member (source={0})", member);
+				}
 			}
+			builder.addAttribute(ATTR_MEMBER, subjects);
 		}
-		builder.addAttribute(ATTR_MEMBER, subjects);
-		handler.handle(builder.build());
+		return handler.handle(builder.build());
 	}
 
 	@Override
diff --git a/src/test/java/com/evolveum/polygon/connector/grouper/test/PlainGroupTests.java b/src/test/java/com/evolveum/polygon/connector/grouper/test/PlainGroupTests.java
index caeb719..b9722e3 100644
--- a/src/test/java/com/evolveum/polygon/connector/grouper/test/PlainGroupTests.java
+++ b/src/test/java/com/evolveum/polygon/connector/grouper/test/PlainGroupTests.java
@@ -120,10 +120,13 @@ public void allGroups() {
 		}
 	}
 
-	@Test(priority = 16, expectedExceptions = IllegalArgumentException.class)
+	@Test(priority = 16)
 	public void allGroupsWithMembers() {
 		results.clear();
 		grouperConnector.executeQuery(PLAIN_GROUP, null, handler, getMembersOptions());
+		for (ConnectorObject group : results) {
+			System.out.println("Found group: " + group);
+		}
 	}
 
 	@Test(priority = 20)