Wikipedia
Cross-promotion is a form of marketing promotion where customers of one product or service are targeted with promotion of a related product. A typical example is cross-media marketing of a brand, for example Oprah Winfrey's promotion on her television show of her books, magazines and website. Cross-promotion may involve two or more companies working together in promoting a service or product, in a way that benefits both. For example, a mobile phone network may work together with a popular music artist and package some of their songs as exclusive ringtones; promoting these ringtones can benefit both the network and the artist. Some major corporations, for example Burger King, have a long history of cross-promotion with a range of partners (see Burger King advertising). The Disney Channel has also made extensive use of cross-promotion. Movie tie-ins are good examples of cross-promotion. On occasion, badly planned cross-promotions can backfire spectacularly such as 1992 Hoover free flights promotion fiasco.
Co-marketing and co-branding are particular forms of cross-promotion.