diff --git a/src/group.h b/src/group.h
index 91ee77e..8c78e5a 100644
--- a/src/group.h
+++ b/src/group.h
@@ -73,7 +73,7 @@ struct Group : GroupPool::PoolItem<&_group_pool> {
 
 	GroupID parent;                         ///< Parent group
 
-	Group(CompanyID owner = INVALID_COMPANY);
+	Group(CompanyID owner = INVALID_COMPANY, GroupID parent = INVALID_GROUP);
 	~Group();
 };
 
diff --git a/src/group_cmd.cpp b/src/group_cmd.cpp
index 12cce41..468694c 100644
--- a/src/group_cmd.cpp
+++ b/src/group_cmd.cpp
@@ -256,9 +256,10 @@ static inline void UpdateNumEngineGroup(const Vehicle *v, GroupID old_g, GroupID
 
 
 
-Group::Group(Owner owner)
+Group::Group(Owner owner, GroupID parent)
 {
 	this->owner = owner;
+	this->parent = parent;
 }
 
 Group::~Group()
@@ -272,7 +273,7 @@ Group::~Group()
  * @param tile unused
  * @param flags type of operation
  * @param p1   vehicle type
- * @param p2   unused
+ * @param p2   ID of parent group
  * @param text unused
  * @return the cost of this operation or an error
  */
@@ -281,13 +282,19 @@ CommandCost CmdCreateGroup(TileIndex tile, DoCommandFlag flags, uint32 p1, uint3
 	VehicleType vt = Extract<VehicleType, 0, 3>(p1);
 	if (!IsCompanyBuildableVehicleType(vt)) return CMD_ERROR;
 
+	const Group *pg = Group::GetIfValid(GB(p2, 0, 16));
+
+	if (pg != NULL) {
+		if (pg->owner != _current_company) return CMD_ERROR;
+		if (pg->vehicle_type != vt) return CMD_ERROR;
+	}
+
 	if (!Group::CanAllocateItem()) return CMD_ERROR;
 
 	if (flags & DC_EXEC) {
-		Group *g = new Group(_current_company);
+		Group *g = new Group(_current_company, pg == NULL ? INVALID_GROUP : p2);
 		g->replace_protection = false;
 		g->vehicle_type = vt;
-		g->parent = INVALID_GROUP;
 
 		_new_group_id = g->index;
 
@@ -475,7 +482,7 @@ CommandCost CmdAddVehicleGroup(TileIndex tile, DoCommandFlag flags, uint32 p1, u
 
 	if (new_g == NEW_GROUP) {
 		/* Create new group. */
-		CommandCost ret = CmdCreateGroup(0, flags, v->type, 0, NULL);
+		CommandCost ret = CmdCreateGroup(0, flags, v->type, INVALID_GROUP, NULL);
 		if (ret.Failed()) return ret;
 
 		new_g = _new_group_id;
diff --git a/src/group_gui.cpp b/src/group_gui.cpp
index 81fb120..bfaeb42 100644
--- a/src/group_gui.cpp
+++ b/src/group_gui.cpp
@@ -636,7 +636,7 @@ public:
 			}
 
 			case WID_GL_CREATE_GROUP: { // Create a new group
-				DoCommandP(0, this->vli.vtype, 0, CMD_CREATE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_CREATE), CcCreateGroup);
+				DoCommandP(0, this->vli.vtype, this->vli.index, CMD_CREATE_GROUP | CMD_MSG(STR_ERROR_GROUP_CAN_T_CREATE), CcCreateGroup);
 				break;
 			}
 
diff --git a/src/script/api/script_group.cpp b/src/script/api/script_group.cpp
index 1e8d6d7..74aa9f4 100644
--- a/src/script/api/script_group.cpp
+++ b/src/script/api/script_group.cpp
@@ -29,7 +29,7 @@
 
 /* static */ ScriptGroup::GroupID ScriptGroup::CreateGroup(ScriptVehicle::VehicleType vehicle_type)
 {
-	if (!ScriptObject::DoCommand(0, (::VehicleType)vehicle_type, 0, CMD_CREATE_GROUP, NULL, &ScriptInstance::DoCommandReturnGroupID)) return GROUP_INVALID;
+	if (!ScriptObject::DoCommand(0, (::VehicleType)vehicle_type, GROUP_INVALID, CMD_CREATE_GROUP, NULL, &ScriptInstance::DoCommandReturnGroupID)) return GROUP_INVALID;
 
 	/* In case of test-mode, we return GroupID 0 */
 	return (ScriptGroup::GroupID)0;