A Commonwealth realm is a sovereign state in which Queen Elizabeth II is the reigning constitutional monarch and head of state. As of 2019, there are 16 Commonwealth realms: Antigua and Barbuda, Australia, The Bahamas, Barbados, Belize, Canada, Grenada, Jamaica, New Zealand, Papua New Guinea, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Solomon Islands, Tuvalu, and the United Kingdom. All 16 Commonwealth realms are members of the Commonwealth of Nations, an intergovernmental organisation of 53 member states. Elizabeth II is Head of the Commonwealth.