We review theories and empirical research on underlying mechanisms of selfhood, awareness, and conscious experience. The mechanisms that have been identified for these phenomena are many and multifarious, lying at many levels of space and time, and complexity and abstractness. Proposals have included the global workspace for conscious information, action and its centrality to self awareness, the role for social information and narrative, and more. We argue that phenomenal experience, whatever it "really is," is probably dependent upon all of these levels simultaneously. We end with two challenges for consciousness research. Both are couched in terms of the dynamics of phenomenal experience. The first is to investigate the sustained dynamics of phenomenal experience; the second is to unveil the way that multi-scale processes in the cognitive system interact to produce that richness of experience. We do not aim to solve the hard problem, but argue that any solution will require this plural characteristic.