Fluid balance measurement (FBM) is a routine intervention in oncology, but accuracy and compliance issues have been documented. This article describes how a medical oncology nursing clinical practice committee used the Iowa Model for Evidence-Based Practice to establish a policy for FBM. Nursing and medical education was performed with emphasis on oncology-specific defaults in a computerized provider order entry system reflecting the new FBM policy. At two months of implementation, the policy effectively demonstrated improved staff compliance and satisfaction, as well as appropriate orders for patients requiring stricter FBM.