Maria was first elected to represent Basingstoke in the 2005 General Election. On becoming a Member of Parliament, Maria was appointed to the Trade and Industry Select Committee. David Cameron appointed her as Shadow Minister for Education in December 2005, then Shadow Minister for Family Welfare in the Department for Work and Pensions in November 2006. Maria moved back to the Education team as Shadow Minister for the Family in July 2007 and remained in post until the 2010 General Election.
Maria served as Secretary of State for Culture, Media and Sport and Minister for Women and Equalities, from September 2012 to April 2014.
Maria was appointed Minister for Disabled People at the Department for Work and Pensions in the Coalition Government in May 2010 and was promoted to Secretary of State for Culture, Media and Sport, and Minister for Women and Equalities, from September 2012 to April 2014. In June 2015 Maria was elected as Chair of the newly established Women and Equalities Select Committee. Maria was nominated for the position by MPs across the House in 2017 and was re-elected unopposed.
In addition to her role as an officer of the APPG on Digital Regulation and Responsibility, Maria holds offices in a number of All-Party Parliamentary Groups, and is currently Co-Chair of the APPG on Domestic Violence; Officer of the APPG on Digital Regulation and Responsibility; Co-Chair of APPG UN Women; and Chair of the APPG on Women in Parliament.
Maria served as Chair of the Commonwealth Parliamentary Association UK and a Member of Select Committee on Administration, Panel of Chairs, Board Member, Parliamentary Office of Science and Technology Board (POST), Speaker's Conference.
She also serves in the board of Governors for Westminster Foundation for Democracy since 2020
Maria was appointed as the Prime Minister's Trade Envoy to Canada in May 2022.