QoS support poses new challenges to multicast routing especially for inter-domain multicast where network QoS characteristics will not be readily available as in intra-domain multicast. Several existing proposals attempt to build QoS-sensitive multicast trees by providing multiple joining paths for a new member using a flooding-based search strategy which has the draw-back of excessive overhead and may not be able to determine which join path is QoS feasible sometimes. In this paper, first we propose a method to propagate QoS information in bidirectional multicast trees to enable better QoS-aware path selection decisions. We then propose an alternative “join point” search strategy that would introduce much less control overhead utilizing the root-based feature of the MASC/BGMP inter-domain multicast architecture. Simulation results show that this strategy is as effective as flooding-based search strategy in finding alternative join points for a new member but with much less ove...