Leal, José PauloQueirós, Ricardo2014-07-032014-07-0320109788493758035http://hdl.handle.net/10400.22/4649Learning systems are evolving from component based and centralized architectures towards service oriented and decentralized architectures. The standardization of e-learning content and interoperability is a powerful force in this evolution. In this chapter we put in perspective the evolution of e-learning systems and standards, and argue that specialized services will play an important role in future learning systems, especially in those targeted for competitive learning.engbook part