The use of bar-code technology to capture data on pharmacists' clinical interventions is described. At a hospital in Northern Ireland, patient-specific information could not be accessed through the pharmacy computer system. A system comprising six hand-held bar-code readers and software for downloading data was purchased. The pharmacy staff selected a range of fields for recording a wide array of data on clinical interventions, including the outcomes. Patient details that could not easily be bar-coded had to be recorded manually. The process was evaluated over three four-week cycles, with the data fields being revised after each cycle and the interventions being judged for their clinical appropriateness and their conformance to inhouse standards. After the third cycle, the need for manual recording of information was eliminated. A total of 857 interventions were made during the three cycles. Performance met or exceeded the standard for 7 (50%) of 14 indicators for the first cycle, 8 (53%) of 15 for the second cycle, and 13 (81%) of 16 for the final cycle. For all three cycles, the majority of the interventions were important and resulted in an improvement in the standard of care. A bar-code-driven data collection system successfully replaced a manual system for documenting pharmacists' clinical interventions.