HACCP is a hazard control method. ISO 22000 is a full food safety management system that contains HACCP and adds management structure, communication and improvement requirements around it. FSSC 22000 is ISO 22000 plus a sector specific prerequisite programme standard and a set of additional requirements, and it is the version recognised by the Global Food Safety Initiative. If a multinational buyer has asked you for GFSI recognised certification, FSSC 22000 is what they mean.