Process Tracing Innovations in Practice: Finding the Middle Path

Evaluation practitioners in the international development sector have given considerable attention in recent years to process tracing as a method for evaluating impact, including discussion of how to assess the relative importance of causal factors. Despite the increasing interest, there is a relative dearth of examples of practical learning and evidence of applying process tracing in practice. This CDI Practice Paper draws on comparative learning from applying three different types of process tracing in international development initiatives. It argues in favour of a ‘middle path’ of applying evidence tests and rubrics to structure evaluative judgements rather than formal Bayesian updating or looser forms of process tracing. It also calls attention to the potential added value of taking a participatory approach, offering practical recommendations for how to do this effectively.