In mammals the glial (or glue) cells contribute some 50% of the volume of the brain. In contrast to the traditional view that they have a purely physically supportive role, research in the last three decades has shown that glia interact morphologically, biochemically and physiologically with neurons during changes in behaviour. The evidence suggests that glia may modulate neuronal activity and thereby influence behaviour. This 1998 book was the first to describe and discuss these neuronal–glial interactions in relation to behaviour. A distinguished set of authors discuss these interactions from a number of viewpoints, and the book will familiarise neuroscientists, zoologists, physiologists and psychologists with the new knowledge of how neurons and glial cells interact with each other to affect behaviour.