This study was designed to test whether there is a lack of social consensus about how stepparents should and will act as parents, and whether individuals in society perceive stepparent roles as similar to or different from the roles of biological and adoptive parents. Two-hundred and forty introductory psychology students were randomly assigned to complete one of three versions (biological parent, adoptive parent, and stepparent) of the Family Role Questionnaire and a demographic instrument. The Family Role Questionnaire consists of 16 vignettes describing a variety of situations calling for some degree of parental behavior. As hypothesized, there was greater variability in subjects' responses to how stepparents, in contrast to biological and adoptive parents, would actually respond and how they should behave in the situations in the vignettes. In addition, respondents thought that stepparents were less obligated and less likely than were biological and adoptive parents to engage in the supportive parental behaviors called for in the situations. Implications for future research and for interventions with members of stepfamilies are discussed.