He was the Labor Party member for Kororoit in the Victorian Legislative Assembly from 2002, prior to that representing the Yan Yean electorate in Melbourne's north from 1992.
He has since worked as a private consultant in both Europe and Australia and is Deputy Chair of the German Australian Business Council.
Before being elected to Parliament, Haermeyer worked for the Victorian ALP Head Office and for Senator Robert Ray, a senior federal cabinet minister at the time.
Haermeyer was elevated to the shadow ministry in 1993 after helping future Victorian Treasurer and Premier, John Brumby win the party leadership after the sudden resignation of Jim Kennan, as Leader of the Opposition.
As shadow minister for Police and Emergency Services, Haermeyer was made law and order positive issues for his party, traditionally an area of conservative strength.