The increasing number of anti-trafficking organizations and funding for anti-trafficking services have greatly out-paced evaluative efforts resulting in critical knowledge gaps, which have been underscored by recent recommendations for the development of greater evaluation capacity in the anti-trafficking field. In response to these calls, this paper reports on the development and feasibility testing of an evaluation protocol to generate practice-based evidence for an anti-trafficking transitional housing program. Guided by formative evaluation and evaluability frameworks, our practitioner-researcher team had two aims: (1) develop an evaluation protocol, and (2) test the protocol with a feasibility trial. To the best of our knowledge, this is one of only a few reports concerning anti-trafficking housing program evaluations, particularly one with many foreign-national survivors as evaluation participants. In addition to presenting evaluation findings, the team herein documented decisions and strategies related to conceptualizing, designing, and conducting the evaluation to offer approaches for future evaluations.