An Ishikawa or cause-and-effect diagram provides a systematic way to visualize the potential causes of a problem or effect. It was developed by Kaoru Ishikawa in 1943 and resembles a fishbone with the problem stated at the head and categories of causes branching out from it. The diagram encourages group participation to determine the root causes of a problem in an orderly format. It helps teams focus on potential causes rather than symptoms and identifies areas for improvement by highlighting causes that appear repeatedly or can be measured and addressed.