Avery Classics has partnered with the Association for Preservation Technology to digitize 500 trade catalogs and make them available to the public through the Building Technology Heritage Library (BTHL) on the Internet Archive. Trade catalogs are an invaluable source of information on building materials, supplies and decoration. Avery Classics has one of the largest collections of architectural trade catalogs in the United States, and its collection is regularly consulted by historic preservationists. This is the first phase of a multi-year project to add Avery’s unique material to the BTHL, which already includes materials from the Canadian Centre for Architecture. The first phase of digitization focused on late-nineteenth century catalogs, along with later catalogs dealing with masonry, metal and paint.