Pharmacist and technician times required for the preparation of parenteral nutrient (PN) solutions were studied before and after the introduction of a software package that is used with an automated compounder. At a 580-bed teaching hospital, work sampling was used to collect data on how time was spent by personnel in the i.v. admixture pharmacy during six-week periods before and after the introduction of software that calculates the quantities of PN solution ingredients on a computer-generated work sheet and prints labels. The second data-collection period began when the software had been in use for four months. In the second study period, there was a significant decrease (28%) in total pharmacist time spent per PN solution; the mean +/- S.D. pharmacist times per PN solution per day for the two study periods were 14.03 +/- 3.24 minutes and 10.12 +/- 1.61 minutes, respectively. There were also significant decreases in pharmacist time spent performing calculations, checking calculations, and typing labels. After introduction of the software, technicians spent significantly less time typing labels and pumping base solutions. Overall, technicians spent significantly less time per PN solution in the second study period (20.15 +/- 3.50 versus 17.82 +/- 1.94 minutes). Use of the software allowed pharmacist staffing in the i.v. admixture pharmacy to be reduced, and the pharmacy resources were reallocated toward the provision of clinical services. The generation of PN labels and calculation worksheets by computer software reduced pharmacist and technician time requirements for PN solution preparation.