Dietrich, Mary was born in 1964 in Ashland, Ohio, United States.
Bachelor, Miami University, Ohio, 1987.
Policy analyst General Accounting Office, 1987—1996. With General Accounting Office United States Senate Agricultural, Nutrition & Forestry Committee, 1996—1998. Professional staff member, Labor, Health, Human Services & Education Subcommittee United States Senate Appropriations Committee, 1998—2002, clerk District of Columbia Subcommittee, 2001—2006, minority clerk, Financial Services & General Government Subcommittee, 2007—2010.
Chief of staff to Sennator Susan Collins United States Senate, since 2010.