Study the value that the upcoming FDA mandated electronic drug labeling HL7 standard will bring to existing and emerging Computerized Provider Order Entry (CPOE) systems and e-prescribing tools on the example of the Regenstrief Medical Gopher CPOE system and on a newly developed completely HL7 standards-based open-source e-prescribing tool used for delivering decision support enabled safe prescribing assistance to practitioners in diverse healthcare settings (incl. small and rural). THRUST 1: Map the Gopher drug knowledge structures to and from the HL7 standard drug knowledge structures, studying the feasibility of automatically importing the public drug knowledge to populate indication-based dosage, SIG defaults, contraindications, interactions, and consequent orders data structures. Study the minimum necessary need for customization, the gain in knowledge coverage and the resulting cost-savings for knowledge maintenance. This experience will be contributed into the standardization of the labeling content. THRUST 2: Based on existing open-source HL7 v3 tools development, create a light-weight open-source prescribing tool that delivers decision support functions (incl. default dosing and dose checks, contraindication and allergy checking, consequent orders) based solely on standards and open terminology and knowledge structures. A focus-group of providers from rural West-Wisconsin and North-Carolina negotiates a minimal set of common requirements to keep the tool light-weight and generalizable. Implement and pilot the tool and evaluate its benefits and costs with (1) a time-series controlled trial demonstrating efficacy to reduce prescribing errors (benefits), (2) time-motion study evaluating usability and cost (in terms of providers' time.) User and patient satisfaction survey will evaluate perceived value. After the pilot, grow the user community to assess the cost of implementation at new sites, demonstrating that standards-based open-source light-weight design can lead to generalizable tools allowing providers to realize the value of CPOE.