On Call Treatment Center is an addiction treatment program located in the heart of Waltham, Massachusetts. Our carefully developed vision of quality clinical care includes day treatment and intensive outpatient (IOP) programs. Our medical, clinical and therapeutic team of experienced and compassionate professionals is available around-the-clock to treat all symptoms associated with addiction as well as the underlying causes. This addiction recovery experience is ideal for individuals who are ready for world-class drug or alcohol treatment who have been suffering from a substance use disorder.