Organizational agility is a significant business capability. Though there have been numerous studies about the effects of information technology (IT) capabilities on organizational agility, there has been limited attention on the enabling effects of IT ambidexterity, namely, the dual capacity to explore and exploit IT resources and practices. We propose that IT ambidexterity enhances organizational agility by facilitating operational ambidexterity, and that the magnitude of facilitation depends on the level of environmental dynamism. We test these relationships utilizing data from a large-scale, matched-pair field survey of business and IT executives. The results confirm that a firm's IT ambidexterity does enhance its organizational agility through the mediated effects of operational ambidexterity, and that the dynamism of a firm's environment affects these relationships.