A succinct and compelling treatise on the bio-psycho-social effects of trauma, and the connections between trauma and addiction, as well as how these conditions facilitate each other. The challenges of working effectively with those struggling with trauma and co-occurring addiction in treatment settings are presented, along with recommended approaches for those in treatment and early addiction recovery.There is a clear relationship between trauma and addiction. Although addiction is not caused by trauma, and trauma is not caused by addiction, it has become increasingly clear that trauma and addiction frequently go together. Extensive research suggests that approximately 50 percent of people with histories of addiction have experienced trauma.Based on different scientific studies, the percentage of people with both trauma and addiction ranges from about 20 percent to as high as 80 percent, with the figure being somewhat higher for women than for men. The connection between trauma and addiction is a two-way street: trauma increases the risk of developing addiction and active addiction increases the likelihood of experiencing trauma.