Current statistics indicate that 75-80% of people worldwide will experience some form of back pain during their lifetime. Lumbar pain is a leading cause of disability - a global public health burden with serious economic implications. Written by internationally renowned spine experts, the 8th volume in the AOSpine Masters series is a concise, state-of-the-art overview on fundamental management strategies and current issues and challenges. The text covers the full age spectrum - from childhood to older adulthood - and contributing factors such as the sacroiliac joints, genetics, and spine infections.