Slurink IAL, et al. - Using national data routinely collected during consultations at centers for sexual health (CSH), researchers wanted a better understanding of risk behaviors among men who have sex with men (MSM) going to CSH and STI and HIV positivity by subgroups. Six classes were identified: “overall low-risk behavior,” “Western origin and multiple sex partners (MSP),” “Non-Western origin and MSP,” “living with HIV,” “group sex and HIV-positive partners,” and “group sex and chemsex.” Findings revealed that that any STI positivity ranged from 14.0% to 35.5% in the overall low-risk behavior class and the group sex and chemsex class, respectively. HIV positivity did not vary significantly among classes. The largest class was the Western origin and MSP class, and it had most of the STI and HIV infections. Evidence of strategies for risk reduction among subgroups involved in risky behavior was seen in the similar HIV positivity among classes. There was considerable STI positivity in all six latent classes, but STI positivity still increased with increased risky behaviors.