This research study hypothesized that specific personality types and decision-making style combinations would be stronger in PMP-certified project managers than nonproject managers. The research conducted to test this hypothesis was a quantitative nonexperimental study examining the personality types and decision-making styles of PMP-certified project managers as compared to nonproject managers. The study used a survey that combined Saucier's Mini-Marker Personality Inventory (MMPI) questionnaire and the General Decision Making Styles Questionnaire, with both having demonstrated reliability and validity. The survey service Qualtrics was used to obtain 238 responses from a sample of PMP-certified project managers and nonproject managers. For this research study, both samples were obtained from the IT industry. Data were analyzed using descriptive statistics, and the predicted relationships were tested using regression analysis. The first hypothesis for this research study looked at the Extroversion personality types and Intuitive decision-making style relationship in PMP-certified project managers compared to nonproject managers. The second hypothesis looked at the Conscientiousness personality types and Rational decision-making style relationship in PMP-certified project managers compared to nonproject manager. In this study, the Hypothesis 1 null hypothesis could not be rejected but Hypothesis 2 could. Additional research into the personality types and decision-making styles of PMP-certified project managers in industries other than IT would provide more generalizability of the research results. Since PMI states that leadership is an expected attribute of a PMP-certified project manager, the relationship between personality types, decision-making styles, and leadership styles of PMP-certified project managers would also be an additional research recommendation.