This newsletter is provided by HIV i-Base in electronic format. This fourth issue contains articles from International AIDS Conference that was held in August 2008 in Mexico. Here are some issues discussed: Taking drugs and harm reduction; Injection Drug Users and HIV: review of clinical treatment; Staphylococcus among IDUs, Abacavir and heart diseases; SMART survey proves suspicions of abacavir leading to cardio-vascular diseases; Colelction of other surveyr conducted among IDUs.