These findings suggest that the profile of the participants whomissed visits or were lost to follow-up is similar to that of high-risk sexually active young Thai MSM.Achieving effective and sustainable programs, i.e., youth-friendly services, is crucial to adequately serving HIV-positive youth. In addition, a multiple-partner variable was a composite of any possible combination of male/transgender sexual partner as well as the UAI variable. These limitations impede the ability to investigate into what partner types the participants predominately have.