The purpose of this chapter is to discuss adult education and the roles self-directed learning, learning through experience, and Communities of Practice (CoPs) play in modern concepts of Adult Education. The chapter begins with a brief discussion of adult education, self-directed learning and key concepts regarding andragogy and learning in adulthood. The major conceptions of CoPs, particularly as they relate to adult education practice, are examined, as well as the intersection of major ideas concerning adult education, self-directed learning and CoPs. Through exploring the ideas of CoPs, knowledge from those who historically and traditionally have not been counted as 'experts' is valued, thus enhancing the knowledge base of adult education and the development of adult learning theory. Paying attention to context, activity and tools allows us to understand how adult learners discover, shape, and make explicit their own knowledge, thus furthering intriguing discussions as to what counts for knowledge and learning in adulthood.