The advent of Web 2.0 and the spread of social software tools have created new and exciting opportunities for designers of digitally-mediated education programs for adults. Whether working in fully online, blended, or face-to-face learning contexts, instructors may now access technologies that allow students and faculty to engage in cooperative and collaborative learning despite being separated in space and time. By supporting the use of interactive methods and multi-media materials, social software offers educators more ways to engage learners than any preceding educational technology. Social software also empowers curriculum designers to more effectively accommodate many of the core principles of adult learning than was possible with earlier e-learning technologies. This article offers a basic introduction to some new possibilities in the design and delivery of digitally-mediated education, and an overview of the compatibility between the capabilities of social software and the principles of adult education.