Our objective was to determine how injection drug users (IDUs) in Baltimore, Maryland obtain and use needles and syringes (NS) for drug injection, before the opening of a needle exchange program (NEP). The method of this study was a cross-sectional structured interview survey in 1992 of active IDUs in a longitudinal study of human immunodeficiency virus (HIV) infection. For 466 IDUs (94.6% black, 83% male), usual sources of NS were "street" dealers (49.6%), pharmacies (29.8%), diabetics (16.3%), friends/neighbors (2.2%), and "shooting galleries" (1.9%). Half (53.5%) reported pharmacy purchase of NS, and 55.6% had diabetic friends/relatives. Twenty-three percent traded drugs, and 5% traded sex for NS. Eighty-eight and two-tenths percent would use a needle exchange program; 24.6% currently own no NS (median owned = 2.2). NS reuse was common (median = three times). Concern about (55.2%) or history of (33.9%) hassle/arrest for NS possession was typical; 81% kept NS at home, and 67% do not carry NS when purchasing drugs. Pharmacy purchasers (versus "street") were less likely to have been jailed, shared NS, or used shooting galleries during the preceding 6 months. In Maryland, although IDUs can legally purchase NS at pharmacist discretion, possession remains illegal; fewer than one-third of IDUs use pharmacies, and most obtain NS from illegal sources. Most IDUs reuse NS, but discard them after several uses. Current patterns of NS acquisition and use in Baltimore are likely to increase HIV transmission. Increased availability and decriminalization of NS possession could decrease the risk of injection-related HIV transmission.