In 1955, an ordinance was adopted setting up the City Manager form of government. Garland Gray, who was an engineer, became the first City Manager working under this newly adopted ordinance, but resigned several months later. Lloyd M. Mitchell then stepped into the City Manager position.

Lloyd M. Mitchell, known to his many friends as "Lefty," was an electrical engineer and avocado rancher, and had spent many successful years in government.  As the Chief of Police, he set up a thorough records system and was known to be an able organizer and proven administrator. He became the second "official" city manager, holding that office from May 5, 1956, to January 10, 1968. Facing expansion in every area and the need for more services to keep up with the population growth, he carefully selected people with training to guide the growth and future of North San Diego County's hub.

Under Mitchell, the following departments were established: Finance, Engineering, Building, Parks & Recreation, Planning, Personnel, and Purchasing.