BGSMath is a collaborative initiative of the research groups in mathematics of four main universities located in the Barcelona area: Universitat de Barcelona (UB), Universitat Autònoma de Barcelona (UAB), Universitat Pompeu Fabra (UPF) and Universitat Politècnica de Catalunya (UPC); and an international research center, Centre de Recerca Matemàtica (CRM). Its primary objective is to provide doctoral and postdoctoral training at the highest level in an international environment. From 2015, BGSMath is a “Unit of Excellence Maria de Maeztu”, a four years grant from the Spanish Government which carries a financial support of 2.000.000 Euros. The BGSMath is the unique unit in mathematics in Spain holding this distinction.