?This work focuses on the characterization of adult lifelong learners’ Personal Learning Environments (PLEs) by implicit and explicit tools of personalization. It aims aims toward creating a system for the development of a learning path for the characterisation of PLE for adult life learners.  The synergy of formal and informal learning in the dynamic construction of a lifelong learner’s PLE is fully explored, with the recognition that the majority of learning, especially for life long learners, occurs outside traditional learning formats. Specifically, this volume discusses the design, implementation, and validation of the SSW4LL (Social Semantic Web for Lifelong Learners) format, and the the SSW4LL system, built on Moodle 2.0 integrated with an adaptive mechanism (conditional activities) and some tools of Social Semantic Web (Semantic MediaWiki, Diigo and Google+). With thoroughly grounded cases studies, this volume makes the case that these systems are suitable to provide a dynamically personalized learning environment to the lifelong learner. All of these environments are fully discussed and cases made for each as a tool for constructing adult learners' PLEs.?