Mr. Bruening's public career started in 1924 in Milwaukee as a Junior Draftsman and he rose through the ranks to become Traffic Engineer and Superintendent of the Bureau of Traffic Engineering and Electrical Services in 1956.  He held this until his retirement in 1972, a total of 48 years in the practice of traffic engineering, all with the City of Milwaukee.  

In the late 1920s Mr. Bruening constantly preached the gospel of the three E's of traffic safety and the necessity of coordination of geometric design and traffic operations.  

His activities in ITE included being Review Editor of the Traffic Engineering Handbook in 1941.  He produced many papers on traffic channelization and signals.  Mr. Bruening was long an advocate of progressive signal timing and employed many innovations in Milwaukee's traffic signal program.  Mr. Bruening also oversaw the first origin and destination survey in Milwaukee in 1946 which led to Milwaukee's freeway system of which he was an early supporter.  He was also an advocate of balanced transportation and many of his transit ideas came to fruition after his retirement, especially in 1976 when Milwaukee went into public ownership of the local transit company.

He joined ITE in 1937 and was active in the Mid-West Section and the Wisconsin Section.  He was also active in the International Municipal Signal Association.  He was a member of the original National Joint Committee on Uniform Traffic Control Devices and served many years in preparing the 1961 and 1971 versions of the "Manual on Uniform Traffic Control Devices.  Mr. Bruening died in January 1994.