Article III of the United States Constitution requires a plaintiff to establish "standing" in order to sue in federal court. In addition to showing an injury-in-fact, plaintiff must also show "causation" and "redressability." In other words, plaintiff must show that defendant is the "cause" of the injury, and that the injury will be redressed by a favorable judicial decision. In this lesson, we examine the requirement of causation (and, to a lesser extent, the requirement of redressability) in an attempt to determine what its means and how it is applied in particular cases. The lesson is intended for students who have studied this topic in class, and who wish to refine their knowledge of the topic.