Lean Enterprise Institute (LEI) is a non-profit training, publishing, and a research center founded in 1997 by James P. Womack, author of the best-selling book Lean Thinking. LEI shares and teaches lean principles, tools, and techniques to minimize waste and maximize value in an organization. This is a great site that describes the fundamentals of lean thinking and provides access to support tools, articles, workbooks, events, and training.