This article introduces comparative process tracing (CPT) as a two-step methodological approach that combines theory, chronology, and comparison. For each studied case, the processes leading "from A to B" are reconstructed and analyzed in terms of ideal-type social mechanisms and then compared by making use of the identified mechanisms and ideal-type periodization. Central elements of CPT are path dependence, critical junctures and focal points, social mechanisms, context, periodization, and counterfactual analysis. The CPT approach is described, discussed, and compared with more formal and deterministic forms of process tracing, which are found to be less fruitful for systematic comparison.