Recommender systems represent a key technology for e-commerce providers such as Google, Amazon, Netflix, Booking.com and Spotify. It is therefore with a certain urgency that researchers are working intensively on making ever more accurate predictions about the products and services users might want to consume next. However, in a paper published recently, Maurizio Ferrari Dacrema, Paolo Cremonesi and Dietmar Jannach were able to show that several critical issues concerning the research methodology are hindering progress in the development of recommender systems. In recognition of their work, they received the Best Full Paper Award at the renowned ACM Conference on Recommender Systems in Copenhagen in September.