The paper REACT: An Approach for Capturing Rationale in Chat Messages by Rana Alkadhi, Jan Ole Johanssen, Emitza Guzman and Bernd Bruegge won the best paper award in the short paper track of the ACM/IEEE International Symposium on Empirical Software Engineering and Measurement (ESEM 2017) in Toronto, Canada. In the paper, the authors present REACT (RationalE Annotations in ChaT messages), a novel lightweight approach to capture rationale in developers' chat messages.