Agile methodologies are changing the way we develop software. Their emphasis on team-oriented development, joint code ownership, and reliance on people rather than predefined processes to guide activities, is transforming software development into a socio-technical process. As methodologies become increasingly more people and team-oriented, there is an urgent need to investigate the personality profiles of software developers and their likely impact on the productivity of the development team. A review of the IS research literature on personality studies found Jungian typology operationalized as Myers-Briggs Type Indicator (MBTI) to be the most popular approach for assessing personality profiles. We compared the Five Factor Model (FFM) of personality, which is currently gaining popularity among personality psychologists, with MBTI. Our analysis, based on extant research literature in personality psychology and group behavior, suggests that FFM not only provides better measures for all factors that are measured by MBTI, but it also allows us to assess Neuroticism, an important personality trait that is of interest to researchers studying work groups, such as the agile development team. Our finding has important implications for researchers studying the agile development process. It is also highly relevant to studies investigating the personality profiles of IS professionals. Thus, our study attempts to bring in fresh insights from Personality Psychology, our reference discipline, to enrich IS research.