This chapter discusses three classes of theories: information-processing theories that build on modular elements, network theories that focus on the distributed access of conscious processing, and globalist theories that combine aspects of these two. It also discusses cognitive or functional models of consciousness with less reference to the burgeoning neuroscientific evidence that increasingly supports the globalist position. Beginning in the 1980s, a number of experimental methods gained currency as means of studying comparable conscious and non-conscious processes. The metaphor of cognitive architectures dates to the 1970s when cognitive psychologists created information-processing models of mental processes. The general position is that consciousness operates as a distributed and flexible system offering nonconscious expert systems global accessibility to information that has a high concurrent value to the organism. Future work should focus on obtaining neuroscientific evidence and corresponding behavioral observations that can address global access as the distinguishing feature of consciousness.