Occupational boundary studies have addressed divisions among workers by examining the process of creating occupational groups and assigning certain attributes to these groups (boundary work). They have, however, neglected intra-occupational dynamics that are also drivers of division and cohesion in the workplace. Using data from participant observation and in-depth interviews in a hospital emergency room with registered nurses, this paper examines the ways that nurses use time management, the ability to be productive while balancing work and breaks well, to distinguish themselves from one another. Using time management, nurses create similarities (cohesion) and differences (divisions) between one another using assessments of a nurse's time management skills. These findings suggests that workplace boundary making may be more dynamic than previous studies have indicated, varying with the status of the person performing the boundary work, the context of the social interaction, and the "audience," in Goffmanian terms, of the performance.