A review of the literature on atypical depression indicated three relatively separate usages for the term: anxiety or phobic symptoms additional to depression, reversed functional shift, and non-endogenous depression. A sample of 160 out-patient depressives was rated on a variety of diagnostic systems measuring these concepts. Inter-relationships between groups selected by the three definitions were found to be low. In addition, although there was moderate consistency within different definitions of endogenous depression and of additional anxiety, reversed functional shift symptoms did not correlate well with each other. These findings suggest that atypical depression may be of limited value as a specific diagnosis within non-psychotic depression.