We studied CMW-1 bone cement with gentamicin in the laboratory and in a randomized clinical study. Palacos bone cement containing gentamicin was used as the control. In the preclinical evaluation, the CMW cement had slightly less mechanical strength. In the clinical study, 51 patients (51 knees) operated on with total knee arthroplasty were studied for 2 years. We used radiostereometric analysis to measure migration of the tibial components, randomized to fixation with either of the two types of cement. The extent and pattern of migration were similar in both groups, and we found no differences in the number, size and extent of radiolucent lines or clinical outcome. No complications occurred. Our findings suggest a need for more studies of CMW-1 bone cement containing gentamicin in a larger cohort of patients.