Gambling disorder is a behavioural addiction that represents the clinical extreme of a spectrum of gambling-related harm. What insights can neuroscientific and neuropsychological methods provide to help understand this condition and improve existing programs for treatment and prevention? This volume describes recent research using an array of contemporary tools including structural and functional brain imaging, and neurocognitive assessment. These analyses consider brain activity and psychological functioning in people with gambling disorder under resting conditions, due to tasks of reward processing and inhibitory control, and as a function of important sources of individual differences including depression and impulsivity. This volume also synthesizes contemporary research using animal models to examine decision-making under uncertainty from a behavioural neuroscience perspective, as well as synthesizing evidence from pharmacological treatments for gambling disorders. These findings complement research to understand substance use disorders and other emerging forms of behavioural addiction. This volume contains contributions from many of the leading research groups in this exciting field. The chapters in this book were originally published as a special issue of International Gambling Studies.