This book is of help to know the magnitude of substance abuse and HIV/AIDS pandemics. The pandemics have brought multidimensional challenge, among youths in particular, and the entire nations in general. However, data regarding the contribution of substance abuse to the spread of HIV/AIDS is scanty in Ethiopia. Thus, the book explores the contribution of youth substance abuse to the spread of HIV/AIDS in Adama town, Ethiopia. The book also comprehends the factors that trigger the youth to substance abuse and the subsequent ramifications. Accordingly, major reasons for abusing substances such as peer influence, psychological and socioeconomic factors are discussed. Hence, psychological, social, economic and health problems are of the effects that stem from substance abuse. Particularly, abusing substances has been aggravating the spread of HIV/AIDS. As a result, the efforts made by some organizations to reduce the rampant prevalence of substance abuse and their adverse impacts arediametrically incompatible with the magnitude of the problem. Thus, the book can be of importance to academicians, policy makers, researchers and others.