John H. Falk is Sea Grant Professor in Free-Choice Learning at Oregon State University and founder and former president of the Institute for Learning Innovation. He is co-author of Thriving in the Knowledge Age, Lessons without Limit, and Free-Choice Science Education, as well as co-editor of In Principle, In Practice: Museums as Learning Institutions. Joe E. Heimlich is a senior research associate at the Institute for Learning Innovation. He has worked in the field of free-choice environmental education for fifteen years. Susan Foutz is a research associate at the Institute for Learning Innovation and is co-editor of In Principle, In Practice.