Parr, who starts his role today (3 January), joins from Cascade Communications, an agency he helped establish in 2011 alongside founder and MD Emma Waterfall.
Before that he spent six months as director at Objective Group, joining from Bell Pottinger, where he led the public affairs division.
He also spent several years in the Cabinet Office before being appointed as then deputy prime minister John Prescott's private secretary in 2003.
Madano was established in London in 2004 and specialises in the energy, pharmaceutical, infrastructure, built environment, financial and government sectors. In 2013 it was acquired by Canadian PR firm NATIONAL Public Relations.