Retrieving personalized care plans from a guideline repository is an ever-increasing need in the medical world, not only for physicians but also for empowered patients. In this chapter, we continue our long-lasting research on ontology-based personalized access to very large collections of multi-version documents by addressing a novel challenge: dealing with multi-version clinical guidelines but also with a multi-version ontology used to support personalized access to them. Efficiency is ensured by a newly introduced annotation scheme for guidelines and solutions to cope with the evolution of ontology structure. The tests performed on a prototype implementation confirm the goodness of the approach. Finally, the chapter proposes an exhaustive analysis of the state of the art in this field and, in the final part, a discussion where we expand our vision to related research themes and possible further developments of our work.