AimMoral distress experienced by nurses in acute care hospitals can adversely impact the affected nurses, their patients and their hospitals; therefore, it is advisable for organizations to establish internal monitoring of moral distress. However, until now, no suitable questionnaire has been available for use in German‐speaking contexts. Hence, the aim of this study was to develop and psychometrically test a German‐language version of the Moral Distress Scale.DesignWe chose a sequential explanatory mixed methods design, followed by a second quantitative cross‐sectional survey.MethodsAn American moral distress scale was chosen, translated, culturally adapted, tested in a pilot study and subsequently used in 2011 to conduct an initial web‐based quantitative cross‐sectional survey of nurses in all inpatient units at five hospitals in Switzerland's German‐speaking region. Data were analysed descriptively and via a Rasch analysis. In 2012, four focus group interviews were conducted with 26 nurses and then evaluated using knowledge maps. The results were used to improve the questionnaire. In 2015, using the revised German‐language instrument, a second survey and Rasch analysis were conducted.ResultsThe descriptive results of the first survey's participants (n = 2153; response rate: 44%) indicated that moral distress is a salient phenomenon in Switzerland. The data from the focus group interviews and the Rasch analysis produced information valuable for the questionnaire's further development. Alongside the data from the second survey's participants (n = 1965; response rate: 40%), the Rasch analysis confirmed the elimination of previous deficiencies on its psychometrics. A Rasch‐scaled German version of the Moral Distress Scale is now available for use.