This study investigates forms of theatre/performance practice and training that can be seen to employ “trance” states or engage the concept of “states of consciousness” as performative practice. Trance is seen here as the result of sustained involvement with detailed information that is structurally organised, invoking imaginative and affective engagements, maintained as interactions between the performer, other performers, the environment and audience of the performance. Trance performance is viewed here through the conceptual lens of dramatic arts practice. Trance practice and performance, across cultural contexts, are analysed as social processes - as elements of power relations that influence the performer, audience and environment of the performance. This study will examine praxis that can be drawn from Stanislavski to Strasberg to Mike Leigh; from Artaud to Beckett and Grotowski; from the Balinese trance performance form Sanghyang Dedari to Channeling practitioners in the U.S. from the 1930s to 1990s; and from traditions of military training, performance violence, and rhetoric associated with the attacks of 9/11 in 2001 in the U.S. and its aftermath.