Bancolombia is the largest commercial bank in Colombia and one of the larg- est in Latin America. This story traces Bancolombia’s journey as it embarked on a wide-ranging digital transformation that encompassed the implementa- tion of an ecosystem strategy and the launch of a neobank—an entirely on- line bank. It highlights how Bancolombia used Nequi to learn how digital-only banks worked and to challenge Bancolombia’s traditional ways of working. It also describes the platform work that Bancolombia did to accomplish its eco- system strategy.