Reciprocal marketing describes a situation in which two businesses promote each other in order to gain a mutual benefit.

The most famous example: Mutual 'Liking' in social networks.

Reciprocal marketing offers a number of potential benefits, especially for individuals and small businesses. It accelerates the process of earning trust of prospects in a new market niche, reduces the cost of attracting new customers, and is inexpensive to implement compared with many traditional marketing schemes.

In  business world, reciprocal marketing is more commonly known as co-op marketing, cross-promotion, or collaborative marketing. It is common in travel, tourism, shopping, and other industries.

Example: Alliances of airlines is an example of reciprocal marketing.