Although most people have experienced word-finding difficulty at one time or another, there are no clinical instruments able to reliably distinguish normal age-related effects from pathology in word-finding impairment. Two experiments were conducted to establish a modified version of the Boston Naming Test (BNT) that includes latency times, the Boston Naming Test of Latencies (BNT-L), in order to improve the instrument's sensitivity to mild to moderate word-finding impairment. Experiment 1: Latency times on the 60-item BNT (Goodglass et al., 2001) for 235 healthy adults' ages 18-89 years were collected on a representative sample. Qualitative features of the BNT items, statistical analyses, IRT, and demographic considerations of age, gender, education, vocabulary, race and culture, helped create a reduced BNT-L version with 15 of the most discriminating items. Statistically sound and sophisticated normative tables are provided that adjust for unseen covariates. Response latencies did not indicate earlier age-related decline in an optimally healthy sample. Experiment 2: Twenty-three patients referred for neuropsychological testing were administered the BNT-L. Patients referred for evaluation of mild cognitive impairment or possible dementia produced significantly different response BNT-L latencies from the healthy sample whereas patients referred for mild brain injury evaluation did not. Normal word-finding problems were discussed in terms of serial stage models of lexical access, as well as in terms of automatic and controlled cognitive processes in younger and older adults. Statistical process for creating a psychometric instrument using latencies is illustrated.