Adelmann joined Openlands in 1980 to coordinate a special program that led to the creation of the Illinois and Michigan Canal National Heritage Corridor, the first federal land designation of its kind. He then founded the Canal Corridor Association in 1982, a model after which 62 heritage areas in 36 states around the country are now based on. In 1988, Adelmann was appointed as head of Openlands. Under his leadership, Openlands launched the 21st Century Open Space Plan, played an instrumental role in establishing Midewin National Tallgrass Prairie, and formed conservation partnerships across the region. Adelmann is a founding member of Chicago Wilderness, chair of the City of Chicago’s Nature and Wildlife Committee, and vice chair of the Center for Humans and Nature among other commissions. His conservation and preservation work in the U.S., China, and Myanmar has earned him prestigious accolades including the Hutchinson Medal from the Chicago Botanic Garden and an honorary doctorate from Lewis University.