Upon graduating high school in Elizabeth City, Lamb enlisted in the US Coast Guard and served from 1942 to 1946 as a chemical warfare specialist.

He served on the boards of the local American Red Cross and NAACP, chaired the board of the Pearl Street Neighborhood House and the Waterbury Negro Business and Professional Men's Association, and served as secretary of the Connecticut Federation of Negro Democratic Clubs for three years.

As treasurer, he administered an annual budget of $300 million and was responsible for the state's bonds, investments, and spending on capital improvements.

[2] In 1964, President Lyndon B. Johnson appointed Lamb a special ambassador to Venezuela to attend the presidential inauguration of Raúl Leoni.

In 1965, Lamb attended the Selma to Montgomery civil rights marches as the State of Connecticut's official representative.

In the 1970s, he served on the Board for State Academic Awards, which granted associate and bachelor degrees to nontraditional students.

The program became Charter Oak State College in 1980 and received accreditation two years later, while Lamb chaired the board.