Following the death of his father, Sidney Winslow Jr. took an increasingly important role in the family company, which had been consolidated into the holding company, United Shoe Machinery Corporation. Winslow went on to expand the company internationally and also to invest heavily in research and development. Under Winslow’s guidance, United eventually grew to have 56 affiliates in 25 countries and its research produced items that were innovative for the shoe industry as a whole.