To become a guild member, a person usually had to go first through a lengthy apprenticeship to learn the trade or business. The apprenticeship period was often fourteen years long, beginning at the...
The usual path to guild membership started with apprenticeship. As a child of six or seven, a person would be apprenticed to a guild master who provided education in exchange for work. The...
They have to. Just like actors have to join the Screen Actors Guild. Well they don't have to, but they do if they want to get any major studio funding.