This is a collection of mainly psychological contributions from those with research and professional interests in co-operative learning, peer tutoring, computer-supported collaborative learning, computer-assisted learning and a variety of other interactive learning situations. Whilst coverage is mainly of learning in educational settings, there are also contributions from organizational settings, including team training in a military context, work, business and employment settings, and scientific problem-solving. secondary and higher education into the domain of work. There is also a focus on learners with special needs.