Straws-in-the-wind, Hoops and Smoking Guns: What can Process Tracing Offer to Impact Evaluation?

This discussion paper, written by Melanie Punton and Katharina Welle, looks at the potential use of Process Tracing in an impact evaluation context. It examines the methodological and theoretical foundations of process tracing and examines two examples of its application in international development interventions.


"Impact evaluation designs based on counterfactual and regularity frameworks frequently encounter limitations when applied in the field of international development. For example, they may not be appropriate to measure initiatives that aim to achieve change through advocacy and policy influence, because the pathways of change are usually unpredictable, highly dependent on changing circumstances and often need to respond to changing goalposts (Tsui, Hearn and Young 2014).

While process tracing has predominantly been applied as a social science research method, the approach is currently being explored in several international development impact evaluations. A recent workshop on process tracing in impact evaluation organised by the Centre for Development Impact (CDI) brought together a number of evaluators who currently apply or intend to apply this method (Barnett and Munslow 2014). Two applications of process tracing are discussed below: a completed evaluation of the Universal Health Care Campaign in Ghana funded by Oxfam GB (Stedman-Bryce 2013); and an ongoing evaluation of the Hunger and Nutrition Commitment Index (HANCI)."


  • What is process tracing?
  • Applying process tracing tests
  • Applications of process tracing within international development impact evaluation
  • Reflections on the application of process tracing in impact evaluation


Punton, M. & Welle, K. (2015). Straws-in-the-wind, Hoops and Smoking Guns: What can Process Tracing Offer to Impact Evaluation?, Centre for Development Impact (CDI). Retrieved from: