Balancing lines-or trying to-dates back to Henry Ford and his assembly line in Highland Park, Michigan, nearly a century ago. Because Ford’s line was paced, or a conveyor line, he had to level load: in other words, each line operator had to have a similar volume of work (time). Otherwise, operators would either be hurrying to keep up with vehicles moving down the conveyor or waiting idly to perform their operation. We have been level-loading assembly lines ever since in our attempt to achieve ‹ow.