The difficulty lies in striking a balance between securing the participation of incumbent operators in a more regulated system and ensuring that conditions offered to operators do not compromise financial sustainability. Negotiations on bus reform are particularly challenging since incumbent operators have political clout and, as has happened in Rio de Janeiro, can potentially suspend all services to put pressure on the authorities. The negotiations with operators of Mexibus failed to incorporate enough microbus owners into the new system or to relocate them into feeder routes. Nonetheless, ensuring inclusion of incumbent operators also came at a significant cost for the project.