We suppose that, stage by stage in causal processes, causes engage in activities that bring about their effects. These should be maximally vividly described when representing causal processes. We thus follow G. E. M. Anscombe, recent work in philosophy of biology on mechanisms, process tracing and realist evaluation in rejecting the Humean approach to causation, which eschews activities. Activities are interpreted as continuous processes afforded by the arrangements of the underlying system in which they take place. We illustrate here how to include activities in our original ‘boxes-and-arrows’ diagrams.