Since joining Waste Management in 2001, Fish has held several key positions in the company, including senior vice president for the Eastern Group, area vice president for Pennsylvania and West Virginia, market area general manager for Massachusetts and Rhode Island, vice president of price management, and director of financial planning and analysis. He became CFO in 2012 and president in July 2016.

Previously, Fish held finance and revenue management positions at Yellow Corporation subsidiary WestEx, Trans World Airlines, and America West Airlines. He began his professional career at KPMG Peat Marwick.

Fish earned a bachelor of science in accounting from Arizona State University before pursuing an MBA in finance at Chicago Booth. He is also a certified public accountant.