Virtual worlds are increasingly incorporated into modern universities and teaching pedagogy. Over 190 higher education institutions world-wide have done teaching in the virtual world of Second Life (SL). This book is based on the first Scandinavian project to experiment with the design and testing of teaching platforms for life long learning in SL. In 2007 it created a virtual island or "sim" in SL called "Kamimo Education Island". The project generated a number of courses taught in Second Life, and instructed educators in the use of SL. This book disseminates the experiences and lessons learned in that project and from other educational projects in SL. The book identifies the gaps in traditional forms of education. It provides a roadmap on issues of: instructional design, learner modelling, building simulations, exploring alternatives to design and integrating tools in education with other learning systems.