In closing, it seems important to add that, when viewed longitudinally, addiction resembles a chronic medical disease. Rehabilitaiton may take several years and improvement rather than cure may be the most reasonable goal. Disappointment at the lack of success in finding an effective cure is common, but a relapsing and remitting course does not necessarily imply failure. Return to treatment may signal continuing efforts and progression toward abstinence. Improvement in current techniques may make remissions longer and relapses shorter. Current work on endogenous opiates (endorphins) may lead to tests which will identify those patients who can achieve drug-free status and those who can function only when maintenance opiates are applied.