The Non-automatic Weighing Instruments (NAWI) Directive was made part of UK law on 1st January 1993.The Directive not only controls the technical and performance characteristics of NAWI, but also specifies which tasks require the use of "controlled" NAWI. One of those specified task is: Weighing patients for the purpose of monitoring, diagnosis and medical treatment.This means that from the 1st of January 2003, when the full effects of the Directive came into force, all new weighing instruments used for medical weighing will have to comply with the requirements of the Directive.These notes are intended to make users and purchasers of medical weighing instruments aware of the requirements.