In 1944, Roy Stryker - now directing a photodocumentary project for the Standard Oil Company of New Jersey - sent Parks on an assignment to document the advantages of oil in the everyday lives of North Americans. This assignment took Parks through New England to Maine where he documented the work and family-life of Hercules Brown, who sold Standard Oil in his general store for twenty years. Parks also documented grease plant workers in Pittsburgh, Pennsylvania and Standard Oil's reach into western Canada.