In the Senate, she serves as the Senate Republican Caucus Chair as a part of the Senate Republican Leadership. Sen. Althoff is the Minority Spokeswoman for the Revenue and Assignments Committees, and also serves on the Transportation, Labor & Commerce, Appropriations II, and Licensed Activities & Pensions Committees. Senator Althoff is part of the Domestic Violence Task Force, the Early Learning Council, the Joint Committee on Administrative Rules (JCAR), the Environmental Caucus, the Midwest Higher Education Commission, and sits on the Executive Committee of the National Conference of State Legislatures.

Senator Althoff has been extremely involved in her community. She currently serves on the MCC Foundation Board, is a member of the Community Development Block Grant Board, and is the Secretary and Treasurer of the McHenry Council of Governments. Past organizations she has been involved with include the McHenry Area Chamber of Commerce, the Fox Waterway Agency, League of Women Voters and more.

She has been named a "Guardian of Small Business" by the National Federation of Independent Business, developed a personnel policy for Fox Waterway Agency, established a Mayors Consortium to identify and coordinate northeastern McHenry County transportation issues, and much more during her career.

Prior to coming to the Senate, Senator Althoff was the McHenry City Mayor from 2001 to 2003. Other positions she has held in her career include a Special Education teacher, an Assistant Administrator with the McHenry Area Chamber of Commerce, a Sales and Marketing Representative, and the McHenry City Clerk and Collector.

She earned her Bachelor's Degree in Education from Illinois State University in 1975, and her Master's Degree in Education from Northeastern Illinois University in 1978.