ISO 22000 and FSSC 22000 are both international standards, designed to provide a food safety management system (FSMS). However, FSSC 22000 is recognized by GFSI. If your suppliers require you to be certified to a GFSI-recognized standard, then FSSC 22000 could be the most suitable for your organization because, in addition to GFSI, the scheme also uses ISO 22000 as the requirement for the management system.