A growing body of research proves that expanding the response to HIV stigma will increase the effectiveness of HIV programming overall, but the response to HIV stigma and discrimination remains relatively small-scale. This working paper, produced by ICRW and the London School of Hygiene and Tropical Medicine, analyzes the factors that encourage an expanded stigma response as well as the barriers that prevent scale-up of these programs. The conclusions of this analysis provide strategic direction for expanding the response to HIV stigma and discrimination.