A Minister of State is a junior cabinet minister in the Canadian Cabinet, usually given specific responsibilities to assist a senior cabinet minister in a specific area.
A secretary of state also holds many similar responsibilities in assisting senior cabinet members, being members of the Ministry and the Queen's Privy Council for Canada. A Secretary of State is legally a Minister of State styled as secretaries. However Secretaries of State are considered junior to ministers of state and are not members of Cabinet.
The title "Minister of State" was created during the government of Pierre Trudeau in 1971 under the Ministries and Ministers of State Act. This act allows for the creation of two different types of ministers of state. Sections 2 through 10 allow for the creation of a ministry of state, which is a temporary government department established by separating parts of departments created by law. A minister of state can be the head of such a ministry. Sections 11 and 12 of the act allow for the creation of a minister of state who "may be assigned by the Governor in Council to assist any minister or ministers having responsibilities for any department or other portion of the public service of Canada in the carrying out of those responsibilities". The latter has become far more common and, by and large, the former has fallen into disuse.