STSMs are aimed at supporting individual mobility, at strengthening the existing networks and fostering collaborations by allowing scientists to visit an institution in an eligible country, namely: another Participating COST Country, an approved COST Near Neighbour Country (NNC) institution or an approved International Partner Country (IPC) institution. A STSM should specifically contribute to the scientific objectives of the COST Action CA15207, while at the same time allowing applicants to learn new techniques or gain access to specific instruments and/or methods not available in their own institutions.