On Wednesday September 11, 2019, Dr. Theo Benos succesfully defended his Ph.D. dissertation, entitled “Essays on Co-operatives’ Idiosyncrasies: Structure, Performance, and Membership” at the Marketing and Consumer Behaviour group (MCB) at Wageningen University. The promotor was Prof dr ir Joost M.E. Pennings, with Dr. ir Nikos Kalogeras and Prof. dr Ko de Ruyter serving as co-promotors.