Early in 1953, Ed bought the building at 43 Fremont Street, Needham Heights, Massachusetts and moved the company there. In August of 1953, Ed suffered a severe heart attack and was unable to actively operate the business for nearly a year.   

Once Ed returned to work, he need to be careful not to over tax himself.  With the business rapidly expanding Ed decided he needed a partner. With this in mind, he persuaded Ralph G. Quilty, a close friend of many years to join the company as a partner. Although Ralph was a chemical engineer and Director of Research for the H. M. Sawyer Company, he liked the challenge that building up the company offered. A partnership was formed, and on January 3rd,  1956, Williamson Electrical Company, Inc. was born.   After three successful years together, Ed Williamson retired November 1, 1959 and Ralph G. Quilty became sole owner.   

Robert L. Tilton joined the company as Shop Foreman in October of 1956.. Bob had served his apprenticeship in the Navy on a submarine tender and was well qualified for the position. Ralph's son, Ralph M. Quilty, joined the company in 1960, having had five years experience in the environmental laboratory at Sylvania Electric Co.   

On September 1, 1967 Ralph G. Quilty retired.  Bob Tilton and Ralph M. Quilty became the owners of Williamson Electrical Company, Inc.   

In the early 1970's Bob's sons, Robert Lee Tilton, Jr. and Brian K. Tilton, along with Ralph's son R. Scott Quilty, joined the company as service technicians.  Over the next several years, they became experts in electric motor, pump and air compressor installation and service.   

In August of 1983, Bob, Sr. purchased Ralph Quilty's half of the business. Ralph and Scott left the company, with the good wishes of the Tiltons, to start their own business selling and servicing generators.   

Williamson Electrical Company, Inc. reformed with Bob, Jr. as President, Brian Tilton as Treasurer and Bob, Sr. and his wife Charlotte (Bob and Brian's mother) as Assistant Treasurers. Bob Jr. and Brian now took a more active role in the company's management and Charlotte, who had been working part-time, extended her hours to take part, as well, in the running of the family business. Bob Jr. secured his Journeyman Electricians License, and later his Master Electricians License under which the company presently operates.  Now under the exclusive management of the Tilton Family, Williamson Electrical Company began to grow at an unprecedented rate doubling its sales and workforce.  
In December of 1991, Bob Sr. and Charlotte retired, turning over the reigns of the business to Bob Jr. and Brian.  

Under Bob and Brian's watchful eye, the business continued to grow.  Seven years later, they had become so large that the building at 43 Fremont Street was no longer sufficient.  They acquired the facilities next door at 51 Fremont Street, and the company expanded its operations to occupy both sites, where it resides today.