Fore Support for RSVP flows across an ATM network has been defined in [BB97, GB97, Ber97a]. Although the use of shortcuts was mentioned in [BB97, Sec. 3.7], and [Ber97a, Sec. 3.6] the current specifications do not address this case in sufficient details so as to allow interoperable implementations. The purpose of this document is to identify issues in using ATM shortcuts for RSVP flows. For purposes of illustrations, the NHRP protocol [LKPC97] will be assumed as the mechanism used to discover shortcuts, and a possible interface between RSVP and NHRP will be outlined. However, it should be noted that other shortcut mechanisms are possible, e.g., PAR [J96], and the general conclusions of this document should also hold in such cases. Since the issue of shortcut discovery is significantly more complex in the multicast case, for which in most instances has not been defined, e.g., NHRP, this document is limited to the case of unicast flows.