Swedish mental health-care services are experiencing a critical shortage of nursing personnel. Researchers suggest that this shortage is due to low levels of job satisfaction. Job satisfaction is frequently studied with the assistance of Herzberg's two-factor theory, and this theory has foremost been explored with studies using quantitative methods. The purpose of the present study was to provide a better understanding of Herzberg's theory in relation to job satisfaction among Swedish mental health nursing personnel within inpatient psychiatric care while using qualitative methodology. This explorative study was based on semistructured interviews with 25 nursing personnel. Qualitative content analysis of interview transcripts identified three main categories: (i) respondents' perception of their work duties, which was perceived as important, meaningful, and demanding; (ii) respondents' relations with colleagues and supervisors, which provided valuable support in everyday work; and (iii) the way the respondents experienced their professional role as mental health nurses, which was described as unclear and vague. Job satisfaction primarily stemmed from working for patients and with other professionals, but their perceived limited progression of responsibilities discouraged a career in the profession. Herzberg's theory proved useful in exploring job satisfaction in this setting, but the findings partly contradict the basic tenets of the theory. Career advancements and incentives, such as salary and compensation, were perceived as lacking, which negatively influenced job satisfaction. Ward managers should establish clinical ladder programmes to recognize and motivate the continuing professional development of nurses. This needs to be coupled with monetary incentives, and linked with increased clinical authority.