When planning a project, you will most likely identify the specific types of resources that each activity will require prior to identifying specifically named resources to perform the work. For example, you have a number of project managers, but before a project is initiated, you may not know which project manager will be available for the new project. These resource types are represented by roles. Generally, roles should be defined for your enterprise, and not for a specific project.
To edit roles, choose Menu | Enterprise | Roles, or click on this icon 
. You will see a pop-up window such as shown in the following screenshot. There will likely be no roles shown at all. This is because by default the screen has a filter so that it displays only the current project's roles. You can change this by clicking on the triangle at the left-hand side of the layout bar and choosing to show All Roles, as illustrated in the following screenshot:
