| # To use an activity structure The activity structure is a hierarchical structure commonly used to break a project down into time-scaled activities. An activity structure is defined by reference to its top activity. The hierarchy of an activity structure consists of all the activities that appear below the top activity. You can define a top activity in the Projects (tppdm6500m000) session. To change a top activity, click on the Specific menu in the Activities (tppss2500m000) session. Use the Activities (tppss2100s000) session to create and maintain activities. You can refine the hierarchy of activities by specifying the parent of each activity you define. Within the activity hierarchy you can define individual activities as: WBS element project cost accounts work packages planning packages Use the Milestones (tppss2501m000) session to create and maintain milestones. Milestones are linked to activities and, if an activity has the Milestone earned value method, milestones enable you to time-phase the budget by use of a version. Milestones can also provide feedback about the progress of customized items built with a PCS project in Manufacturing. Additionally, milestones can trigger installment s for invoicing. Use the Activity Baseline (tppss2120m000) session to create and maintain baseline (a snapshot) for activities, see To use baselines in Project. Note An WBS element is part of the work breakdown structure, which can be the top of the activity structure. In the WBS you define the project scope. In the lower levels of the activity structure you can use the project cost accounts, planning packages, and/or work packages to define the actual work that is needed to establish that scope. Related topics To use distributed amounts |