Study Design A pilot double-blind randomized controlled trial (RCT). Background The effectiveness of physical therapy for femoroacetabular impingement syndrome (FAIS) is unknown. Objectives To determine the feasibility of an RCT investigating the effectiveness of a physical therapy intervention for FAIS. Methods Participants were 17 women and 7 men (mean ± SD age, 37 ± 8 years; body mass index, 25.4 ± 3.4 kg/m2) with FAIS who received physical therapy interventions provided over 12 weeks. The FAIS-specific physical therapy group received personalized progressive strengthening and functional retraining. The control group received standardized stretching exercises. In addition, both groups received manual therapy, progressive physical activity, and education. The primary outcome was feasibility, including integrity of the protocol, recruitment and retention, outcome measures, randomization procedure, and sample-size estimate. Secondary outcomes included hip pain and function (international Hip Outcome Tool-33 [iHOT-33]) and hip muscle strength. Poststudy interviews were conducted to determine potential improvements for future studies. Results Twenty-four (100%) patients with known eligibility agreed to participate. Four patients (17%) were lost to follow-up. All participants and the tester remained blinded, and the control intervention was acceptable to participants. The between-group mean differences in change scores were 16 (95% confidence interval [CI]: -9, 38) for the iHOT-33 and 0.24 (95% CI: 0.02, 0.47) Nm/kg for hip adduction strength, favoring the FAIS-specific physical therapy group. Using an effect size of 0.61, between-group improvements for the iHOT-33 suggest that 144 participants are required for a full-scale RCT. Conclusion A full-scale RCT of physical therapy for FAIS is feasible. A FAIS-specific physical therapy program has the potential for a moderate to large positive effect on hip pain, function, and hip adductor strength. Level of Evidence Therapy, level 2b. J Orthop Sports Phys Ther 2018;48(4):307-315. doi:10.2519/jospt.2018.7941.