This chapter organizes into three sections diverse strategies for the empirical investigation of dreaming. The first is addressed to the question of how the dream becomes known to the individual and the investigator though the process of recall. The second deals with the assumption that dreaming reflects or represents in an explicable fashion factors such as personality traits, interpersonal events, and physiological activity. The third discusses two hypotheses: (1) that dreaming is a psychological process which can be studied apart from the neurophysiological process of sleep and (2) that dreaming is a functional process, specifically that dreaming is adaptive. For purposes of discussion, dreaming refers to a psychological process (analogous to thinking) presumably inherent in the neurophysiological activity of the sleeping nervous system. Dream or dream experience refers to conscious awareness of dreaming while it is occurring. The dream report refers to the communication about a dream.