This the propose to use the Multiphase Optimization Strategy Trial (MOST) design to identify an anal HSIL screening algorithm which is most suitable in terms of effectiveness, efficiency, and economy. Specifically, The Investigators will use a factorial design as the main strategy in the MOST, as this allows the evaluation of multiple intervention components that are candidates for ultimate inclusion in the algorithm. The Investigators will then implement the most suitable anal HSIL screening algorithm in the clinic, using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework to guide its design, implementation, and evaluation. An interrupted time series will be used to compare anal HSIL screening uptake among men who have sex with men clients in the clinic, prior to and after the implementation of the new anal HSIL screening algorithm, and mixed-methods approaches will be used to evaluate components of the RE-AIM framework.