I'm currently researching medieval architecture, and trying to look more into the design of cathedrals etc. and I know that it is not like construction and design nowadays, but involved a number of contributors. Namely the master stonemason, and members of various other guilds, but would like more information on what guilds exactly and their contribution to design. Am I right in believing that the structural form and proportions were calculated by the master stonemason and then the detail and 'art work' was carried out my different craftsmen from the required field?