A Defense of the Constitutions of Government of the United States of America is a three volume work by John Adams published in 1787–1788. The work was written while Adams was serving as the American ambassador in London. In Britain and in previous postings in France and the Netherlands Adams had confronted several criticisms of the government systems used by the American states. Adams started the work prior to the writing of the Constitution of the United States and the work is not a defense of that document, but rather of the various state constitutions that were in place in 1787.