Causal Loop Diagram
A Causal Loop Diagram is a visual representation and reference that helps to understand cause and effect connections. It works best when people work together to create it, and the collaboration is used to tease out the common understanding of a problem. I like using them with teams to help think about moving beyond the Quick Fix mentality to deeper, more systemic solutions.
You can see examples of CLDs in action in these anti-patterns, where the Causal Loop Diagram makes more obvious the detrimental affect they can have:

Example of a Causal Loop Diagram