The organization sets up, runs and keeps processes for evaluating whether it complies with legal and other requirements. It decides how often and by what methods compliance is evaluated, carries out the evaluation and acts where needed, keeps up its knowledge and understanding of where it stands on compliance, and retains documented information on the results.
This control maps to 15 controls across 13 other frameworks. If you already hold one of them, the evidence you collected for it is the starting point here rather than new work.