Massachusetts General Hospital will take the unusual step of questioning all patients about their use of alcohol and illegal drugs beginning this fall, whether they are checking in for knee surgery or visiting the emergency department with the flu. How often have you had six or more drinks on one occasion, caregivers will ask, or used an illegal drug in the past year? If the battery of four questions reveals a possible addiction, doctors can summon a special team to conduct a "bedside intervention" and, if needed, arrange treatment. The mandatory screening program is part of a broad plan to improve addiction treatment at the Boston teaching hospital and its community health centers and is an example of an expanding national and statewide effort to reach substance abusers earlier and in mainstream medical settings.