The updated Ontario MOHLTC Laboratory Requisition (OHIP) includes a new section specifically designed to capture information required to properly interpret and act upon bilirubin measurements in the newborn. Babies may be placed at risk if communication with the laboratory is imprecise. Conversely, ’Critical’ calls may be initiated which would have been considered unnecessary had the laboratory received (clinical) information permitting proper interpretation such as information concerning phototherapy or previous results. Potentially ’Critical’ results or results indicating the need for therapy are determined in relation to the child’s age in hours1 which should be provided on the requisition. For truly ’Critical’ results, it is important that we have a contact number for the responsible clinician which is effective 24 hrs. per day. As a back-up there is a field in which to provide the telephone number of the parent or care giver which should be the home number effective nights and at the weekend. This is important should an ’on-call’ clinician be required to manage the baby. From time to time we encounter a situation in which a nurse visits a home to procure a sample which is submitted to our laboratory without the name of a clinician and without contact information. Clearly this is a problem if a ’Critical’ value is generated. Nurses performing home visits on behalf of a physician should be instructed to provide the necessary information. Kernicterus2 is fortunately a rare condition but cases still occur.