From 1890 until 1893 Taylor worked as a general manager and a consulting engineer to management for the Manufacturing Investment Company of Philadelphia, a company that operated large paper mills in Maine and Wisconsin. He spent time as a plant manager in Maine. In 1893, Taylor opened an independent consulting practice in Philadelphia. His business card read "Consulting Engineer - Systematizing Shop Management and Manufacturing Costs a Specialty". Through these consulting experiences, Taylor perfected his management system. In 1898 he joined Bethlehem Steel in order to solve an expensive machine-shop capacity problem. As a result, he and Maunsel White, with a team of assistants, developed high speed steel, paving the way for greatly increased mass production. Taylor was forced to leave Bethlehem Steel in 1901 after discord with other managers.