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<ManualTopic ID="/baanerp/tp/onlinemanual/000024" xml:lang="en">
	<Header>
		<Title xmlns:ssa="http://www.ssaglobal.com" xmlns:HTML="http://www.w3.org/TR/REC-html40">To use an activity structure</Title>
		<Keyword><Level1>activities</Level1>
		</Keyword>
		<Keyword><Level1>structure</Level1>
			<Level2>project</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, click on the Specific menu in the <GUIRef href="/baanerp/tp/pss/tppss2500m000" role="session">Activities (tppss2500m000)</GUIRef> session.</Paragraph>
		<List><ListIntro>Use the <GUIRef href="/baanerp/tp/pss/tppss2100s000" role="session">Activities (tppss2100s000)</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 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/tppss2501m000" role="session">Milestones (tppss2501m000)</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 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 <GUIRef href="/baanerp/ti" role="package">Manufacturing</GUIRef>. Additionally, milestones can trigger <Link href="/baanerp/tp/glossary/glossary#000089" role="glossary">installment</Link> s 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 Project</Link>.</Paragraph>
		<Note><SectionTitle>Note</SectionTitle>
			<Paragraph>An <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>
