'''Arrow diagramming method''' (ADM) is a network diagramming technique in which activities are represented by arrows.<ref>CPM in Construction – A Manual for General Contractors(Copyright 1965 by the Associated General Contractors of America)</ref>. ADM is also known as the activity-on-arrow (AOA) method.
ADM is used for schedulingscheding activities in a [[project plan]]. Precedence relationships between activities are represented by circles connected by one or more arrows. The length of the arrow represents the duration of the relevant activity. ADM only shows finish-to-start relationships, meaning that each activity is completed before the successor activity starts.
Sometimes a "dummy task" is added, to represent a dependency between tasks, which does not represent any activity.
The[[ImageThe event represented by the circular node consumes neither time nor resources. ▼
Use of ADM as a common project management practice has declined with the adoption of computer-based scheduling tools. In addition, the precedence diagram method (PDM), or activity-on-node, is often favored over ADM.
<ref>A Guide to the Project Management Body of Knowledge, 4th Edition: ANSI/PMI 99-001-2008 (copyright Project Management Institute, Inc. 2008)</ref>
ADM network drawing technique the start and end of each node or event is connected to an arrow.
The start of the arrow comes out of a node while the tip of the arrow goes into a node. Between the two nodes lies an arrow that represents the activity.
▲The event represented by the circular node consumes neither time nor resources.
* A node is a specific, definable achievement in the project.
