Software use in many organizations has spread vertically. I present evidence that applications that are widely used in organizations have at least three distinct patterns of use: one for individual contributors, one for managers, and one for executives. Use within each of these groups is shaped by its particular activity and incentive structures. Interaction among group members promotes shared social conventions and feature use. When designing, acquiring, or supporting such an application, the best approach could be to treat it as three distinct applications. The applications discussed include shared calendars, email, application-sharing, shared workspaces, browsers and desktop videoconferencing.