Aim 2. Compare the HIV testing preferences within each high-risk population to the characteristics of existing testing options and identify feasible, more preferred alternatives. Hypothesis: Multiple distinct and feasible testing options can be identified that are predicted to better match the preferences of high-risk populations. The investigators will use latent class analysis of DCE choice data from Aim 1 to identify distinct sets of testing preferences within each high-risk population. Comparisons of each risk group's preferences with the characteristics of existing testing options will be used to identify, separately for each group, a set of two or more feasible new testing options, or variations of existing testing options, that are predicted to be more preferred and whose uptake can be evaluated in a randomized controlled trial (RCT) in Aim 3.