Wikipedia
Co-promotion is a marketing practice that allows two or more companies to combine their sales force in order to promote a product under the same brand name and price with a single marketing strategy. It is considered as one of the two major forms of joint marketing (Kalb 1988). Co-marketing is the other form and these terms are often confused. It is made through an agreement (the co-promotion agreement) which requires a lot of collaboration between the sales & marketing organisations of both companies. One of the partners usually has a licence to exploit the product and the other partner is the originator or licensor. It helps the less developed areas of a company to be covered by the partner company's strengths and therefore to expand the share of voice in the marketplace for a product. Through co-promotion, a collaborative strategy, the consumer attraction is increased. It is a way co-exploiting products.