Consciousness is, perhaps, the aspect of our mental lives that is the most perplexing for both psychologists and philosophers. Daniel Dennett has described it as 'both the most obvious and the most mysterious feature of our minds' and attempts at definition often seem to move in circles. Thomas Nagel famously remarked that 'without consciousness the mind-body problem would be much less interesting. With consciousness it seems hopeless.'. These observations might suggest that consciousness - indefinable and mysterious - falls outside the scope of rational enquiry, defying both scientific and philosophical investigation. In reality, however, the topic has been a focus of psychological investigation since William James and is increasingly vital in philosophical research. This book illustrates the various, interdisciplinary approaches to the problem, providing both pointers to a solution and a summary of the key positions.