There is an ongoing need for continuing professional education (CPE) in the rapidly changing field of HIV care, but the best instructional methods remain a subject of debate. This study assessed the effects of training at an AIDS Education and Training Center (AETC) over an 18-month period. Health care professionals (HCP) who attended more than one training event showed small but significant improvements over time in HIV-related clinical practice behaviors. The type of training also predicted self-reported practice behavior, with interactive trainings and individual consultations associated with greater change, and intensive clinical training activities associated with a faster rate of change but not better scores on the self-reported behavior measure. Participants also reported high levels of satisfaction, knowledge improvement, and intention to change after each training event; however, these results were unrelated to whether trainees actually reported improved practice behavior.