We analyze how firms from emerging markets upgrade their capabilities to improve their international competitiveness. We argue that firms use a combination methods, the four-I mechanisms, to upgrade their capabilities – imitation, integration, incorporation, and internal development – and that the underdevelopment of emerging markets affects this catching-up process. We propose that initially, as laggards in global competition, firms are more inclined to imitate products and services from more sophisticated firms, leveraging the relatively weak intellectual property protection of their home countries and aiming to serve low-income consumers. As they catch up, firms are more likely to integrate best practices through alliances to obtain technologies, or to learn by serving as suppliers of more sophisticated firms. Firms then incorporate best practices by acquiring technologies or firms that own sophisticated knowledge. Finally, as they catch up to leaders, firms focus more on internal development of capabilities. We highlight how the four-I mechanisms evolve with the development stages of firms and emerging economies.