The endangered Lower Keys marsh rabbit (LKMR; Sylvilagus palustris hefneri) exists as a metapopulation in patches of wetland habitat in the Lower Florida Keys, USA. The recovery plan for the LKMR recommends reintroducing rabbits to unoccupied but potentially suitable patches. The effectiveness of such reintroductions has not been evaluated. We translocated 12 and 7 rabbits fitted with radiotransmitters to patches of apparently suitable vegetation on Little Pine and Water Key during 2002 and 2004, respectively. Our radiotelemetry-based study monitored survival, site fidelity, and reproduction. We observed high survival (81% of known-fate rabbits on Little Pine and 100% on Water Key), fidelity to release sites (mean distance from release sites <120 m for 12 of 15 rabbits monitored), and evidence of reproduction during the first 6 months postrelease. Our results suggest reintroductions could be an effective conservation tool for LKMRs. If reintroductions are to have broader application, however, we recommend managers combine habitat management and land acquisition to bolster source populations and create additional release sites.