The present call for proposals aims at supporting public procurers in purchasing new and improved solutions, products and services in areas of grand societal challenges as defined by Innovation Union communication. This objective is to be realised through establishing trans-national networks to enable Contracting Authorities (as defined by Directives 2004/18/EC and 2004/17/EC) and organizations supporting innovation procurement: to offset the additional risks and costs, to collaborate to create a critical mass, to test the feasibility and implementation modalities of a future EU support scheme.