This work examines and critically evaluates the proposal that phenomenal properties, or the subjective qualities of experience, present a formidable challenge for the mind-body identity theory. Physicalism per se is construed as being ontically committed only to phenomena which can be made epistemically and cognitively available in the third person; observed and understood from within an objective frame of reference. Further, the identity relation between the mental and the physical is taken to be strict identity; the mental phenomena in question just are the physical phenomena on which, ex hypothesi, they supervene. The problem of phenomenal properties has two basic strands. The first is the problem of how they are causally related to the physical; if they are not physical phenomena, by what causal mechanism might they be related to physical phenomena? One of the motivating considerations which led to the identity thesis was that it appeared to remove this problem. Our interest, however, is in evaluating the arguments which purport to establish that phenomenal properties are, indeed, distinct from the physical.