Objective: The purpose of this study was to describe early career health sciences information professionals’ self-reported attainment of the Medical Library Association (MLA) Competencies for Lifelong Learning and Professional Success and to investigate the various methods by which participants developed these competencies. Methods: A SurveyMonkey survey was designed to ascertain participants’demographic information and their competency attainment. ‘‘Early career’’ health information professionals were defined as those with less than five years of professional experience. Participants were asked to rate each of the seven competencies on a five-point Likert scale regarding their level of agreement with the statement, ‘‘I have demonstrated this competency.’’ Participants who responded positively were then asked to indicate how they acquired the competency on a multiple-choice, multiple-answer list. Free-text fields were provided for general comments and for participants to elaborate on their answers. The survey was distributed through the MLA email discussion list and other related email discussion lists. Participation was anonymous. Results: One hundred eighty-seven responses were received. Out of those 187 respondents, 95 completed the entire survey. The majority of early career health sciences information professionals agreed that they had attained all 7 competencies. Of the various methods used to develop competencies, the most selected method was formal library and information studies education. Participants were least likely to report attaining competencies via mentoring, volunteering, or internships. Participants reported the highest level of confidence in having attained the ‘‘Health Sciences Information Services’’ competency, and the lowest level of confidence in having attained the ‘‘Research, Analysis, and Interpretation’’ competency. Conclusions: These results contribute to the ongoing discussions regarding proposed changes to the MLA competencies. The results may also inform the development of educational and professional development opportunities for prospective or early career health information professionals.