An Ishikawa diagram (also known as a fishbone or cause-and-effect diagram) is a tool used to identify and analyze the root causes and sources of a risk. It helps the risk manager gain a deeper understanding of the risk source and likelihood. (Reference: PMBOK Guide, 6th Edition, p. 139) An Ishikawa diagram, also known as a fishbone diagram or a cause-and-effect diagram, is a tool that can help the risk manager to analyze the root causes of a risk and to identify the factors that influence its occurrence and impact. An Ishikawa diagram can also help to visualize the relationships among different causes and to prioritize the most significant ones. By developing and employing an Ishikawa diagram, the risk manager can gain a deeper understanding of the source and likelihood of the risk and plan appropriate responses accordingly. References: The Standard for Risk Management in Portfolios, Programs, and Projects, page 72; PMBOK Guide, 6th edition, page 398.