William Banzhaf retired in 2007 from his position as President of the Sustainable Forestry Initiative Inc., independent 501(c)3 not-for-profit organization.  A 15-member multi-stakeholder board of directors and a seven person staff oversee and implement the Sustainable Forestry Initiative ® Standard, the most widely used forest certification standard in North America (over 200,000,000 acres third party certified). Prior to his work with the SFI, he served as the Executive Vice President for the Society of American Foresters (SAF) from 1988 to 2002. In addition, Banzhaf served as President of George Banzhaf & Company, a consulting firm with a national practice specializing in forest land valuation and present and future projections of sustainable wood supply for the forest products industry, from 1967 to 1988.

Banzhaf has held or holds positions on the boards of a numerous professional organizations including the Sustainable Forestry Board, Roundtable on Sustainable Forests, Council of Engineering and Scientific Society Executives, Pinchot Institute of Conservation, Seventh American Forest Congress, Natural Resource Council of America, USDA, National Commission on Wildfire and National Council on Private Forests, the Michigan Nature Conservancy, and the Association of Consulting Foresters. He currently lectures at Northern Michigan University on Leadership.

He graduated from the University of Michigan in 1967 with a BS in Forestry (one year graduate degree) and from the University of Colorado in 1964 with a BA in History/Political Science.