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Appointments to the Order of the British Empire were discontinued in those Commonwealth realms that established a national system of honours and awards such as the Order of Australia, the Order of Canada, and the New Zealand Order of Merit. In many of these systems, the different levels of award and honour reflect the Imperial system they replaced. Canada, Australia, and New Zealand all have (in increasing level of precedence) Members of, Officers of, and Companions to (rather than Commanders of) their respective orders, with both Australia and New Zealand having Knights and Dames as their highest classes.

What were the highest class?
Knights and Dames