Since 2012 Hilmar has held the post of elected councillor for urban development, building, housing, and transport for the German Association of Cities and the City Association of North Rhine-Westphalia. He studied spatial planning in Dortmund and urban and regional planning in Ankara.Hilmar worked as a freelance urban planner in Dortmund and took his second state examination in urban design in Frankfurt am Main in 1991. Until 1994, he worked for the GTZ as a planning advisor on urban development in Kathmandu. Until 2000, he was head of a division at Dresden City Planning Office. Hilmar also worked in Berlin from 2000 to 2012, where he was responsible for urban design, approval of all building projects, and legal affairs. From 2007 to 2010 he worked for GIZ and headed the Program for Sustainable Urban Development in Syria.