The results of a 2008 survey by the U.S. Pharmacopeia (USP) Safe Medication Use Expert Committee assessing the use of standardized i.v. drug concentrations at U.S. health care institutions are presented. To evaluate progress toward the goal of standardizing and limiting the number of i.v. infusion concentrations of high-risk medications, particularly those commonly used in pediatric patients, a USP-appointed expert committee surveyed a nationally representative sample of hospital and health-system pharmacy directors; 229 usable survey responses and 174 requested lists of routinely used or "standard" concentrations (i.e., those designed to meet the needs of at least 90% of the target adult, pediatric, and neonatal populations) were received. The survey responses indicated that multiple concentrations of high-risk drugs are still commonly used; in some instances, as many as four standard concentrations of a single medication were reported to be in use for a particular age group. Depending on the drug and target group, the proportion of respondents reporting the use of one standard concentration for a given drug ranged from 15% to 79%. The survey data informed and helped focus the USP expert committee's efforts to develop recommended standard concentrations for 10 high-alert drugs. Also presented in this article are general principles drafted by the USP committee to guide the development of local and national standard concentrations. The results of a national USP survey indicate that many institutions do not use standard i.v. infusion concentrations of commonly used high-risk medications in adult, pediatric, or neonatal patient populations.