This chapter presents an overview of the term 'flow' and the altered states of consciousness. Experiences of infinity and limitlessness are shared by flow and transcendent experiences. During flow and transcendence, people often experience a sense of unity with everything. This feeling of unity is not characteristic of normal states of consciousness. Both trance and flow are temporary states of consciousness that involve transition. The experiences among archaic shamans, poets in antiquity and contemporary jazz musicians have always been characteristic of mystical enlightenment. In Western countries flow offers a socially acceptable way to connect with the unconscious and spiritual realm at the same time as major religions are losing their hold on the collective imagination. The idea of profane or secular transcendence is supported by Maslow's statement that he had often met non-religious people who reported having peak experiences, when Maslow himself felt that they were really talking about core-religious or transcendence experiences.