This report provides a global perspective on the ARV marketplace in low- and middle-income countries in 2012 and outlines CHAI’s expectations on how the market will evolve over the next five years, including the potential impact of the 2013 WHO Guidelines on patient volumes and regimen trends. The report contains three sections: Market Overview, Adult Market Trends and Pediatric Market Trends. The Market Overview section summarizes the size of the ARV market in both patient and dollar terms, and shows that the market continues to grow in low- and middle income countries. The Adult Market Trends and Pediatric Market Trends sections highlight CHAI’s expectations for the market based on our most recent global ARV forecast, which was finalized in May 2013. This provides a baseline perspective on how the market will evolve in the absence of major policy shifts. Recognizing, however, that WHO issued a new set of guidelines on the diagnosis, care and treatment of HIV in July 2013, CHAI has also provided a series of scenario analyses that estimate the potential impact of the new guidelines on the global market, including the impact of the increased number of patients eligible for treatment and regimen shifts. The extent to which the new recommendations impact patient volumes and ARV trends will become clearer as countries review the new WHO guidelines over the coming months and determine if and how to implement each recommendation. We close both sections by looking beyond the new guidelines at other factors that could impact the market in the coming years.