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<ManualTopic ID="/baanerp/tp/onlinemanual/000024" xml:lang="en">
   <Header>
      <Title>To use an activity structure</Title>
      <Keyword type="header" order="d1e2264436">
         <Level1>Activity structure</Level1>
         <Level2>Project</Level2>
      </Keyword>
      <Keyword type="header" order="d1e2264442">
         <Level1>Project</Level1>
         <Level2>activity structure</Level2>
      </Keyword>
   </Header>
   <GeneralSection>
      <Paragraph>The activity structure is
		a hierarchical structure commonly used to break a project down into time-scaled <Link href="/baanerp/tp/glossary/glossary#000005" role="glossary">activities</Link>.</Paragraph>
      <Paragraph>An activity structure is
		defined by reference to its <Link href="/baanerp/tp/glossary/glossary#000078" role="glossary">top</Link> 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 <GUIRef href="/baanerp/tp/pdm/tppdm6500m000" role="session">Projects (tppdm6500m000)</GUIRef> session. To change a top activity, use the <Link href="/baanerp/tc/glossary/glossary#specific" role="glossary">appropriate</Link> menu in the <GUIRef href="/baanerp/tp/pss/tppss2500m100" role="session">Activities-Overview (tppss2500m100)</GUIRef> session.</Paragraph>
      <List>
         <ListIntro>Use the <GUIRef href="/baanerp/tp/pss/tppss2100m000" role="session">Activities (tppss2100m000)</GUIRef> 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
		  such as:</ListIntro>
         <ListItem> 
            <Link href="/baanerp/tp/glossary/glossary#000085" role="glossary">WBS element</Link>
         </ListItem>
         <ListItem> 
            <Link href="/baanerp/tp/glossary/glossary#000338" role="glossary">project cost accounts</Link>
         </ListItem>
         <ListItem> 
            <Link href="/baanerp/tp/glossary/glossary#WorkPackag_tp" role="glossary">work packages</Link>
         </ListItem>
         <ListItem> 
            <Link href="/baanerp/tp/glossary/glossary#PlanniPackag_tp" role="glossary">planning packages</Link>
         </ListItem>
      </List>
      <Paragraph>Use the <GUIRef href="/baanerp/tp/pss/tppss2101m000" role="session">Milestones (tppss2101m000)</GUIRef> session to create and maintain <Link href="/baanerp/tp/glossary/glossary#Milestone_tp" role="glossary">milestones</Link>. Milestones are linked to activities and, if an
		activity has the <GUIRef href="/baanerp/tp/domains/pss.mevl#milst" role="option">Milestone</GUIRef> 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 <GUIRef href="/baanerp/ti" role="package">Manufacturing</GUIRef>. Additionally,
		milestones can trigger <Link href="/baanerp/tp/glossary/glossary#000089" role="glossary">installments</Link> for invoicing.</Paragraph>
      <Paragraph>Use the <GUIRef href="/baanerp/tp/pss/tppss2120m000" role="session">Activity Baseline (tppss2120m000)</GUIRef> session to create and maintain baseline (a snapshot)
		for activities, see <Link href="/baanerp/tp/onlinemanual/000025" role="manual">To use baselines in <GUIRef href="/baanerp/tp" role="package">Project</GUIRef>
         </Link>.</Paragraph>
      <Note>
         <SectionTitle>Note</SectionTitle>
         <Paragraph>A <Link href="/baanerp/tp/glossary/glossary#000085" role="glossary">WBS element</Link> 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.</Paragraph>
      </Note>
   </GeneralSection>
   <RelatedTopics>
      <SectionTitle>Related topics</SectionTitle>
      <RelTopic>
         <Link href="/baanerp/tp/onlinemanual/000072" role="manual">To use distributed amounts</Link>
      </RelTopic>
   </RelatedTopics>
</ManualTopic>