SMART, the International Association of Sheet Metal, Air, Rail and Transportation Workers, is one of North America’s most dynamic and diverse unions with 208,000 members. SMART’s members ensure the quality of the air we breathe, promote energy efficiency, produce and provide the vital services that move products to market and passengers to their destinations. We are sheet metal workers, service technicians, bus operators, engineers, conductors, sign workers, welders, production employees and more.