James Cashman has been performing and overseeing construction work in the greater Boston area since his days as a high school student at the Thayer Academy in Braintree, Massachusetts. While working his way up from laborer to field supervisor with the Boston construction company M. Solimando, he studied business at the Boston University School of Management. James Cashman established his first construction company in 1974 and earned his bachelor of science in business administration in 1977.

He would go on to found and lead several marine contracting companies over the course of his career, gaining extensive experience in fields ranging from mega marine infratructure projects , dredging to bridge removal. For the past 25 years, he has served as president of the Cashman Equipment Corp. This barge rental and marine contracting company owns and operates the largest fleet of offshore deck barges in the world. They also operate a fleet of vessels that include inland barges, cranes barges, accommodation barges, and oil spill recovery barges, most of which operate in the US and caribean.