Visit their main website at www.imba.com.  Information from the I.M.B.A. website: Mountain bicycling has become popular around the world, and most land managers and trail-user groups have come to acknowledge the legitimacy of responsible mountain bicycling on public lands. IMBA offers many programs designed to bring bike advocates and land managers together in productive partnerships.
As acceptance of mountain biking has grown, many of the early blanket closures have been reversed, and regulations are now more site-specific and nuanced. There are currently a number of official partnerships between IMBA, IMBA-affiliated clubs, and land management agencies not only to promote mountain biking, but to use mountain bikes to promote and improve public land use. Visit our online resources pages for much more on IMBA`s advocacy programs.