Implementation of a Neonatal Pain Assessment Instrument at a Neonatal Intensive Care Unit - A Quality Improvement Project Abstract. Background: Optimal pain management is necessary in order to not jeopardize the development of preterm neonates. Aim: Implementation and evaluation of systematic and best possible pain assessment with the Bernese Pain Scale for Neonates for all preterm and sick neonates of a neonatal intensive care unit by nursing staff. Methods: The educational concept is based on three key strategies: knowledge translation (group- and one-on-one training), reflection (case conferences) and clinical training. The frequency of the use of the Pain Score was recorded before (T0) and after implementation (T1) and six months after completion of the project (T2). Results: Before the implementation (T0) the use of the Bernese Pain Scale was regulated by an internal guideline but its application could not be verified during the baseline period (fulfillment rate of 0 %). After implementation (T1) at least one assessment per shift per neonate could be achieved in 99.1 % of the cases. Nurses conducted 210 assessments on 38 neonates in T1. In follow-up (T2) six months after implementation fulfillment rate of 100 % in 34 neonates was achieved with 188 pain assessments. Conclusions: This implementation strategy was successful in establishing the assessment instrument in clinical practice.