Building and strengthening the co-operative economy is also advanced by creating partnerships, co-operative consortia and trade relationships between co-operatives at every scale, local to global. Strong economic co-operation at all levels facilitates the sustainability and growth of the co-operative movement.

Co-operative-to-co-operative or Coop2Coop trade is the most direct economic expression of this 6th Principle. It happens when co-operative businesses collaborate within an industry or economic sector, often via sectoral federations, to advance shared economic goals. Coop2Coop trade includes aggregated purchasing and supply chain contracts with other co-operatives, which benefits both the supplier co-operative and the purchaser.

Successful examples of Coop2Coop trade are the relationships between agricultural co-operatives and consumer co-operatives in countries like Japan and the role of co-operatives in developing the fair trade movement. The emphasis on relationship building and supply chain development between purchasing and consumer co-operatives in the global north and farmer and producer co-operatives in the global south has had a powerful impact in increasing market share for co-operatively produced commodities. This strengthens the livelihood of co-operative farmers and enables wider social development through the application of the fair trade premium.