McDonald was born in Koblenz, Germany, while his father was stationed there with the U.S. military.

McDonald co-founded Global Water and later founded the Institute for Multi-Track Diplomacy.

But he and Diamond held that there were several other practical types of Diplomacy which could strengthen the relationships of peoples and governments, these included business to business, religious group to religious group, academic group diplomacy, professional peace building diplomacy, activism, research, training, and philanthropy.

Subsequent tracks of Diplomacy have been added to include women's groups, sports and the arts.

Throughout its 25 years, IMTD's mission embraced a wide range of peace building activities from a peace-building soccer/football tour throughout contested Kashmir, to water sharing agreements crafted by engineers between states which were technically at war, to conflict resolution training and reconciliation efforts around the world.