Apprenticeship
Apprenticeship with a length of 3 or 4 years are the most common ones. The certificate awarded after successfully completing a 3 or 4-year apprenticeship is called "Certificat Fédérale de Capacité" (), "Eidgenössisches Fähigkeitszeugnis" (EFZ) or "Attestato federale di capacità" (AFC).
United Association
In the first half of the century, the United Association moved to formalize apprenticeship training programs, including making a five-year apprenticeship mandatory in 1921, and in 1938 holding that all apprentices be members of the United Association and attend related training classes. Its National Plumbing Apprenticeship Plan of 1936 was the first set of standards governing apprenticeship to win approval of the federal government.