We derive a 4-step process of occupational sex segregation from a case study of restructuring in a large American bank This change was occasioned by a restructuring initiative that created new positions. Through interviews with employees and direct observation of work in four geographic regions, we identify four factors that underlie the process of resegregation: Managers built gendered assumptions into the new jobs; employees responded to these cues and to the characteristics of the jobs; management made job assignments that were consistent with both their assumptions and employees `choices; and both managers and employees developed shared gender norms associated with the new positions.