This study investigated whether a correlation exists between the principal’s leadership style and both a) performance level and b) the principal’s effectiveness in schools in Dubai. It also investigated whether the correlations change according to the principal’s gender, years of experience, and the level of the school (primary, intermediate, and secondary). Data on principals’ leadership styles and effectiveness were collected through Avolio and Bass’ (1995) Multifactor Leadership Questionnaire (MLQ) completed by teachers in 34 government schools. Data on school performance were obtained from the 2010 Dubai Schools Inspection Bureau report. The study found that the transformational leadership style was most frequently employed, followed by the transactional style, and then the passive or avoidant style. The study found a positive correlation between the principal leadership style and his/her effectiveness, but found no correlation with school performance. Finally, principal style and effectiveness differed according to the principal’s gender and the level of the school, but not according to the principal’s years of experience. Findings of this study open a new area of research on school principalship, performance, and effectiveness in the UAE.