A survey of Freud's writings about 'secondary revision' is made. Critical analysis of the material reveals that this concept denotes three different psychological functions, and is often used inconsistently. It is suggested differentiating between 'primary revision', which is a part of the dream-work, 'secondary revision', which takes place after a tentative dream has been already prepared, and 'tertiary revision', which operates after awakening. Presentation of the rationale for this differentiation and the functional analysis of the new concepts are attempted.