Professional magicians have collaborated to prevent exposure of techniques for performing magic. The Society of American Magicians (SAM) was founded in 1902. Harry Houdini served as its president from 1917 to 1926. From its beginning SAM sought to prevent exposure of magicians’ tricks. SAM helped to develop and enforce the Magician’s Code or Oath. A typical statement of it:

As a magician I promise to never reveal the secret of any illusion to a non-magician, without first swearing them to the Magician’s Oath. I promise never to perform any illusion for any non-magician, without first practicing the effect until I can perform it well enough to maintain the illusion of magic.

Adhering to this code fosters one’s access to knowledge about magic tricks and membership in magicians’ organizations. The Magician’s Code, often described as an ethical principle, also functions economically to preserve magicians’ professional capital.