The Commonwealth Heads of Government Meeting (CHOGM; or) is a  summit meeting of the heads of government from all Commonwealth nations. Every two years the meeting is held in a different member state and is chaired by that nation's respective Prime Minister or President who becomes the Commonwealth Chair-in-Office until the next meeting. Queen Elizabeth II, who is the Head of the Commonwealth, attended every CHOGM beginning with Ottawa in 1973 until Perth in 2011, although her formal participa tion only began in 1997. However, she was represented by the Prince of Wales at the 2013 meeting as the 87-year-old monarch was curtailing her overseas travel. The Queen continues to attend CHOGMs held in Europe and was present at the 2015 summit in Malta and is expected to attend the 2018 CHOGM which is to be held in London.