Colorado Mountain School - Mountaineering, climbing and extreme mountaineering courses. (****)
Colorado Outward Bound School - Learn wilderness leadership and outdoor skills.
EMS - Eastern Mountain Sports - Rock climbing, mountaineering, outdoor skills and more.
Hangliding - #1 school in the USA!
NOLS - The National Outdoor Leadership School - The nation's preeminent teacher of outdoor skills & leadership. Courses last from 10 days to full semesters worldwide. Sea kayaking, sailing, backpacking, mountaineering, kayaking, horsepacking or canoeing. (not yet rated)
Nature Awareness School - Spiritual and survival skills courses in Virginia.
OutwardBound.com - (not yet rated)
Outdoor Wilderness Leadership School - OWLS specializes in corporate developement and team building through rock climbing, rappelling, kayaking, mountain biking, backpacking, and wilderness leadership.
Worldwatch Institute - Dedicated to fostering the evolution of an environmentally sustainable society, one in which human needs are met in ways that do not threaten the health of the natural environment or the prospects of future generations.