A legal transaction or transactional act, under German jurisprudence, is the main type of lawful legal act ‘by which legal subjects can change the legal positions of themselves or other persons intentionally’. The concept is important in civil law jurisdictions based on or influenced by the German law of obligations, like Austria, Switzerland, Greece, Turkey, South Korea, and Japan. It also makes its appearance in a few Napoleonic jurisdictions that have partially received German legal theory, like Italy or Portugal.