ObjectivesA clear development process and scientifically validated clinical practice competencies in standard critical care nursing (SCCN) have not yet been developed in Japan. Thus, this study aimed to develop a consensus-based set of SCCN competencies to provide a framework for critical care nursing education, training and evaluation.DesignMultistep, modified Delphi study (a systematic review, focus group interviews, a three-round web-based Delphi survey and an external validation process).ParticipantsA systematic review of 23 studies, focus group interviews by 12 experts, a Delphi survey by 239 critical care experts (physicians, nurses and physical therapists) and an external validation by 5 experts (physicians and nurses).ResultsA systematic review identified 685 unique competencies. The focus group interviews resulted in the addition of 3 performance indicator items, a synthesis of 2 subdomains and 10 elements. Of the 239 participants, 218 (91.2%), 209 (98.9%) and 201 (96.2%) responded in rounds 1, 2 and 3 of the Delphi survey, respectively. After round 3, 57 items were below the consensus level and were removed in the final round. External validation process feedback was received from experts after two revisions to ensure that the final competencies were valid, applicable, useful and clear. The final set of competencies was classified into 6 domains, 26 subdomains, 99 elements and 525 performance indicators.ConclusionsThis study found a set of SCCN competencies after a multistep, modified Delphi study. The results of this study are robust, and the competency framework can be used in multiple areas to improve clinical practice, including the assessment, training and certification of standard critical care nurses.