In 1921, a small dedicated group of Purchasing Agents met at the Rice Hotel in downtown Houston to form the Purchasing Agents Association of Houston. From that small group who blazed a trail, the President's gavel has passed to 101 Presidents, all who have helped make ISM-Houston one of the largest and most dynamic ISM Chapters in the world. ISM offers the Certified Professional in Supply Chain Management (CPSM), as well as the Certified Professional in Supplier Diversity (CPSD). LEARN. NETWORK. GROW.