In 1996, Stirnemann began making small artworks the size of commercial trading cards. An exhibition of 1200 of Stirnemann's cards ran at his second-hand bookshop and gallery INK.art&text in Zurich, Switzerland between 23 April and 31 May 1997. The exhibition ended with a trading session.Bossardt, Fredi. "Trading Cards", WOZ, 18 April 1997. The ATC project was intended to allow people from different backgrounds to participate in an ongoing art project, which was not part of the art market. Selling or buying ATCs clearly contradicts the initial idea. Instead, people would meet at trading sessions and exchange their art work in a democratic face to face situation. Anybody can participate in the project and all techniques are allowed.Osborne, Catherine. „Keeping it real: Public art for people“, Broken Pencil - The guide to alternative culture in Canada 3, 1999. ATCs are produced in various media, including dry media (pencils, pens, markers, etc.), wet media (watercolor, acrylic paints, etc.), paper media (in the form of collage, papercuts, found objects, etc.), or even metals, fiber, wax and other materials.
