After receiving his PhD, Walker taught in Boston and
Oxford, Ohio. In 1969, he moved to
Indiana University of Pennsylvania (IUP), where he served as professor of economics and chair of the economics department until his retirement in 1998. He specialized in the field of
microeconomics. In 1998, he received the Distinguished University Professor Award. After retiring he served as professor emeritus of economics. The Donald A. Walker Department of Economics Scholarship Fund at IUP is named after him. == Personal life ==