| 1199SEIU in Watertown, MA | AMERIGROUP in Watertown, MA |
| APS Healthcare in Watertown, MA | Aetna in Watertown, MA |
| Alliance in Watertown, MA | AmeriHealth in Watertown, MA |
| American Behavioral in Watertown, MA | Beech Street in Watertown, MA |
| Behavioral Health Systems in Watertown, MA | BlueCross and/or BlueShield in Watertown, MA |
| CCN in Watertown, MA | CHIPA/College Health in Watertown, MA |
| Cascade Health in Watertown, MA | Ceridian in Watertown, MA |
| ChoiceCare in Watertown, MA | Cigna in Watertown, MA |
| ComPsych in Watertown, MA | Corphealth in Watertown, MA |
| Coventry in Watertown, MA | First Choice Health in Watertown, MA |
| First Health in Watertown, MA | GHI/Group Health Incorporated in Watertown, MA |
| Great-West in Watertown, MA | Guardian in Watertown, MA |
| HFN in Watertown, MA | HIP/Health Plan of New York in Watertown, MA |
| Harvard Pilgrim Health Care in Watertown, MA | Health Net in Watertown, MA |
| Holman Group in Watertown, MA | Horizon Healthcare in Watertown, MA |
| Humana in Watertown, MA | Integrated Health Plan in Watertown, MA |
| Interplan in Watertown, MA | Kaiser in Watertown, MA |
| LifeWise in Watertown, MA | MAMSI in Watertown, MA |
| MHN/Managed Health Network in Watertown, MA | Magellan Behavioral Health in Watertown, MA |
| MagnaCare in Watertown, MA | Medica in Watertown, MA |
| Medicaid in Watertown, MA | Medical Mutual in Watertown, MA |
| Medicare in Watertown, MA | Multiplan in Watertown, MA |
| NCPPO in Watertown, MA | ODS in Watertown, MA |
| Oxford in Watertown, MA | PHCS/Private Health Care Systems in Watertown, MA |
| PPOM in Watertown, MA | PacifiCare in Watertown, MA |
| PacificSource in Watertown, MA | PreferredOne in Watertown, MA |
| Providence in Watertown, MA | Sloans Lake in Watertown, MA |
| TRICARE in Watertown, MA | TriWest0127 in Watertown, MA |
| Tufts in Watertown, MA | UniCare in Watertown, MA |
| Uniform in Watertown, MA | United in Watertown, MA |
| VMC in Watertown, MA | ValueOptions in Watertown, MA |
| WellPoint in Watertown, MA |