Three qualitative notions play an important role in current debates about causal explanation. Specificity: ‘the notion we are trying to capture is that the state of C exerts a fine-grained kind of control over which state of E is realized’ (Woodward 2010, 305). Proportionality: ‘proportional in the sense that they should be just “enough” for their effects, neither omitting too much relevant detail nor containing too much irrelevant detail’ (Woodward 2010, 297). Stability: ‘the stability of this relationship of counterfactual dependence has to do with whether it would continue to hold in a range of other background circumstances’ (Woodward 2010, 292). Causal information theory applies Shannon information measures to the results of interventions on a causal graph. It allows us to clarify these three concepts and define measures of them.