Cohesion is architected with a set of modules. Each module contains a group of related tables that can be edited and viewed using the Cohesion Editor and Cohesion Report tools.  Additional custom Servlets can be added to any module. Role-Based security controls access at the module, Servlet, table, and column levels. If a report is setup to provide a link to a Servlet, but the user does not have access to the Servlet, the links will not appear. Modules make it easy to start new projects by installing only the essential modules.