Three folk psychology predispositions towards group behavior were proposed: (a) The folk psychologist breaks group behavior down into the actions of individuals; (b) He attributes group and group member behavior to causes internal to the group, and ignores situation causes; and (c) He attributes behavior to fixed rather than alterable causes. It was suggested that family research is susceptible to these predispositions. Accordingly, a sample of current family research, all the family listings in Psychological Abstracts, 45, 1971, 1-6, that represented data based research were classified. The results of classification were: (a) Individual family members' behavior received attention in 69% of the cases, the family group received attention in only 4% of the cases, and the situation was never the recipient of effect; (b) in 61% of the cases, the implied cause was internal to the group, in 12% of the cases, the implied cause was external to the group; (c) in 19% of the cases, the implied cause was alterable, in 42% of the cases, the implied cause cause was fixed. Implications of these predispositions for family therapy were discussed. (Author)