Before entering politics, she had written a great deal on multiculturalism, women's issues, constitutional, civil and human rights. She had also been involved in the constitutional debate in Canada. She was a member of the National Coalition on the Constitution; Member of the Council for Canadian Unity; a member of the Federal Task Force on Multiculturalism; a member of the Premier of Ontario's Advisory Group on the Constitution (Charlottetown Accord) and Vice-Chair of the Ontario Canada Committee (the “Yes Committee”) in the Charlottetown Referendum. Politics In the provincial election of 1995, Castrilli was elected as a Liberal in the northwest Toronto riding of Downsview, defeating incumbent New Democrat Anthony Perruzza. The general election was won by the Progressive Conservatives, and Castrilli became the Opposition Critic for Colleges and Universities, also serving as Opposition Critic for Women's Issues Critic to the Attorney-General. She was subsequently appointed Chair of the Standing Committee on Social Development and a member of the Tripartite Legislative Committee of the Ontario Government on the Calgary Constitutional Accord, overseeing the Calgary Accord constitutional referendum in Ontario. When Lyn McLeod resigned as Liberal leader in 1996, Castrilli initially entered the race to succeed her, ultimately giving her support to eventual winner Dalton McGuinty. (See Ontario Liberal Leadership Conventions.) Castrilli initially planned to run as a Liberal in the 1999 provincial election, but was defeated for the party's nomination in York Centre by fellow caucus member Monte Kwinter. The Progressive Conservative government had previously reduced the number of constituencies from 130 to 103, forcing several incumbent Members of Provincial Parliament (MPPs) to compete against one another for renomination. On the last sitting day of the legislature, Castrilli crossed the floor to sit as a Progressive Conservative. She won the PC nomination in the Parkdale—High Park constituency, and lost to Liberal MPP Gerard Kennedy in the general election. Kennedy and Castrilli were both candidates for the Liberal party leadership in 1996. Later life She was appointed by Premier Mike Harris as the director of "Partnership with Ontarians", an office created to promote the province for international business. In the federal election of 2004, Castrilli supported Conservative Party candidate Michael Mostyn. Later in the year, she was co-chair of Jim Flaherty's unsuccessful bid to lead the provincial Tories. She is also the founding partner of Castrilli Law, a director of SEADAC Strategic Consultants Inc., a director of the Ontario Association of Former