Background: Awareness about adequate sedation in mechanically ventilated patients has increased in recent years. The use of a sedation scale to continually evaluate the patient's response to sedation may promote earlier extubation and may subsequently have a positive effect on the length of stay in the intensive care unit (ICU). The Richmond Agitation-Sedation Scale (RASS) provides 10 well-defined levels divided into two different segments, including criteria for levels of sedation and agitation. Previous studies of the RASS have shown it to have strong reliability and validity. The aim of this study was to translate the RASS into Swedish and to test the inter-rater reliability of the scale in a Swedish ICU. Methods: A translation of the RASS from English into Swedish was carried out, including back-translation, critical review and pilot testing. The inter-rater reliability testing was conducted in a general ICU at a university hospital in the south of Sweden, including 15 patients mechanically ventilated and sedated. Forty in-pair assessments using the Swedish version of the RASS were performed and the inter-rater reliability was tested using weighted statistics (linear weighting). Result: The translation of the RASS was successful and the Swedish version was found to be satisfactory and applicable in the ICU. When tested for inter-rater reliability, the weighed value was 0.86. Conclusion: This study indicates that the Swedish version of the RASS is applicable with good inter-rater reliability, suggesting that the RASS can be useful for sedation assessment of patients mechanically ventilated in Swedish general ICUs.