What does it mean if you experience verbal hallucinations? Are you mad or divinely inspired? And what does the content of your hallucinations signify? Is it meaningful? Or is it un-understandable nonsense, an epiphenomenon of biological processes that points only to a neuropsychological address and a diagnosis?

Leudar & Thomas explore how people explain verbal hallucinations. They consider the voice hearers, the psychiatrist, the press and the public. They provide accounts from voice hearers with a psychiatric diagnosis and from those without. They document what these experiences have been held to mean in the past and what meaning we place on them now. To Socrates, it meant that he was hearing a wise and divine daemon. To the contemporary British press, it typically means madness and unreasoning violence. To psychiatrists it is often a symptom of psychosis to be suppressed with medication. To voice hearers nowadays it is usually as mundane as most inner speech, similarly influencing their behaviour by directing and judging.

The authors aim to describe experiences and explicitly step back from explanations. They conclude that voices do not necessarily indicate insanity any more than thinking, imagining or seeing do: they are an unusual kind of private speech. So they have meaning to the hearer which can be understood if one listens.

This book is part of the growing body of opinion that believes hallucinations to be not random events but metaphors related to the hearer's personality and the stresses that precipitate his or her condition. This has therapeutic implications, recognised by cognitive techniques that draw out the structure and meaning of the voices. But Leudar & Thomas depart from some cognitive therapists' approach on one point: they have no wish to challenge the voice hearer's explanation of the voices, preferring instead to elucidate how the phenomenon is rooted in the patient's past experiences and life history.

The book offers a wide and detailed perspective. It struggles at times to bring material from diverse sources into focus and to maintain a coherent argument. But the content is fascinating and leads to a clear and important message. Leuder & Thomas sum up nicely the clinical perspective from which we have come: “The question ‘Who is speaking?’ is answered by ‘Nobody, it's just hallucinations’. And ‘What do the voices mean?’ is answered by ‘They mean your illness, nothing else’ ”. Through their book they remind us that, by listening to the patient, we will discover where to go.