The fourth edition of the Summer School on "Methodologies for Impact Evaluation" was held at LISER on the 10th-12^th July 2017 and co-sponsored by the European Social Fund Project (ESF), the Ministry of Labour, Employment and the Social and Solidarity Economy of Luxembourg, ARCO (Action Research for CO-Development). It was primarily directed to consultants, doctoral post-doctoral students, as well as academics interested in methods used in evidence-based policy making.

Professors Donald B. Rubin, Fabrizia Mealli and Alfonso Flores-Lagunes were among the instructors of the summer school. Participants had the opportunity to appraise cutting-edge methodologies directly from scholars who are pushing the methodological boundaries. The school was also a valuable opportunity for networking with other impact evaluation professionals coming from diverse fields. In particular, all the keynote speakers were able to relate and interact with the audience to create a comfortable environment.

The summer school was then followed by two day International Workshop on "Causal Inference, Program Evaluation and External Validity" (13-14 July, 2017), focused on advances in the design and analysis of experimental and observational studies for causal effects. Participants came from Spain, Italy, Germany, Luxembourg, Belgium, Netherlands, USA and the United Kingdom. They were invited to present novel papers related to analyses characterised by atypical data structures, interference among units, and external validity of program evaluation studies.