This study used meta-analysis to examine cumulatively needle exchange program (NEP) change/comparison data from 47 studies between 1988 and 2001, based on data collected between 1986 and 1997. The research question posed was: Is NEP attendance associated with reductions in risky needle-related behaviors? Results indicated that needle sharing (r = -.189), variations on the outcome measure of needle sharing (r = -.161), and needle lending/borrowing (r = -.194) consistently declined among NEP attenders, suggesting the NEPs are effective in reducing risky needle-related behaviors of IDUs. The meta-analytic results lend support to the harm-reduction philosophy often used as the rationale for the establishment and maintenance of NEPs.