Jason MacDonald was most recently director of communications for Aboriginal Affairs Minister Bernard Valcourt, and previous worked under former minister John Duncan.
MacDonald replaces Andrew MacDougall, who is leaving as director of communications in the Prime Minister’s Office for a public relations job in the U.K.
MacDonald will be Harper's eighth director of communications in as many years, and arrives as the government is facing one of its greatest public-relations challenges yet — the Senate spending scandal.
MacDonald ran unsuccessfully for Ontario's Progressive Conservatives in the 2011 provincial election.
Harper has made a number of changes to his staff since the controversial departure in May of his chief of staff Nigel Wright. Longtime aide Ray Novak took over from Wright, and will be assisted by new deputy chief of staff Jenni Byrne, one of the party's top operatives.
MacDougall has congratulated MacDonald, saying on Twitter that he is professional, experienced and able to handle tough files.
MacDonald worked previously for Carleton University and the CBC.
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