Dr. Sheehan graduated from Tufts University School of Medicine in 1975 and has been in practice for 43 years. He completed a residency at St Elizabeths Medical Center. He currently practices at Lester John Sheehan Jr MD and is affiliated with St Elizabeth's Medical Center. Dr. Sheehan accepts multiple insurance plans including Aetna, Harvard Pilgrim and Tufts Health Plan. Dr. Sheehan also practices at Sheehan & Zahner Orthopaedic Assoc in Brighton, MA.