This book offers a new theoretical framework within which to understand "the mind-body problem". The crux of this problem is phenomenal experience, which Thomas Nagel famously described as "what it is like" to be a certain living creature. David Chalmers refers to the problem of "what-it-is-like" as "the hard problem" of consciousness and claims that this problem is so "hard" that investigators have either just ignored the issue completely, investigated a similar (but distinct) problem, or claimed that there is literally nothing to investigate - that phenomenal experience is illusory. This book contends that phenomenal experience is both very real and very important. Two specific "biological naturalist" views are considered in depth. One of these two views, in particular, seems to be free from problems; adopting something along the lines of this view might finally allow us to make sense of the mind-body problem. An essential read for anyone who believes that nosatisfactory solution to "the mind-body problem" has yet been discovered.