Estimator and construction engineer on concrete bridges, 1905-1907. Associated with Sanford E. Thompson, Boston, 1907-1915. Partner The Thompson & Lichtner Company, 1916, vice-president and treasurer since 1925.
President The Wm. O. Lichtner Associates, management counsellors, 1932-1941. Chief engineering consultant, War Production Board, 1942. Chief of technicians, American Technical Mission to Brazil, 1942.
Resigned Government service, May 1943, to resume engineering business. Lecturer on management and labor problems at Massachusetts Institute Technology, Harvard, Syracuse University, etc.