The paper presents an ontology-based framework for capturing learning context related information important for personalization of both learning objects (LOs) and learning designs (LDs). The central part of the framework is the LO Context ontology, that bridges a learning content ontology and a LD ontology. The LO context ontology is aimed at capturing information about the actual usage of a LO inside a LD, such as the learning activity the LO was used in, the pedagogical role assumed by the LO (e.g. exercise), the learner?s features (represented in the form of the learner model) and the like. Furthermore we suggest the architecture of an adaptive educational system that leverages the proposed approach to enable personalization and reuse of LOs and LDs.