Retained foreign bodies after surgery are a rare but serious error. Prevention has traditionally been accomplished by manually counting surgical sponges and instruments used at the beginning and end of the case. However, prior research has found that this method does not reliably prevent errors. This randomized trial compared the incidence of misplaced and miscounted sponges in procedures using standard manual count with procedures where a novel bar-coded surgical sponge was used. Although use of bar-coded sponges reduced both misplaced and miscounted sponges, the counting process took more time, and clinicians had mixed opinions on the utility of the new technology. Bar coding has been previously used to reduce errors in medication administration and in laboratory specimen identification.