The purpose of this thesis is to investigate which personality types are most common among Swedish naval officers and whether there are differences between officer branches. The results are intended to support the growing need for personnel to achieve increased operational capability in the Swedish Navy. The means of investigation is an online survey and subsequent analysis with both quantitative and qualitative methods. John Holland's RIASEC theory has been used as a dialogue partner in the study. The six personality types within the RIASEC framework were translated into operational indicators and used for the personality test and to guide the analysis. The results indicate two primary personality types who are representative among Swedish naval officers in general and two secondary types that show signs of differences between branches which includes some activities that reduce enthusiasm for work.