This is the fifth edition of CISA, with the past editions organized by the Autonomous University of Madrid (Madrid, 2012), the University of Barcelona (Barcelona, 2013), the University of the Basque Country (Vitoria, 2015) and the IMEDEA and the University of the Balearic Islands (Palma de Mallorca, 2018). CISA meetings are fantastic opportunities for researchers involved in the study of evolutionary biology in the Iberian Peninsula to discuss, exchange, and debate ideas, as well as to establish long-lasting collaborations. These meetings have also been remarkable seed banks for postdoctoral endeavours, and the perfect substrate to build strong and skilled research groups within a regional scale. However, the COVID pandemic put a halt to their development for longer than expected (last was in 2018). Therefore, one of the main aims of this symposium is allowing the 'reconnection' of Iberian senior researchers, early career researchers and PhD students with a focus on evolutionary biology and systematics in their research, while having fun in the remarkable city life of Madrid.