Complex engineering projects typically face unique challenges that demand both exploring innovative solutions and exploiting existing capabilities. However, it is difficult to manage both exploitation and exploration in the same organizational unit owing to the different organizational support required for each. The solutions to managing the tension involve separating the two approaches into separate organizational units—structural separation, or separating by time—temporal separation, or by creating an organizational context that empowers employees to pursue both. Structural separation may not work because of the predominant need for integration at project level due to the fragmented nature of the construction industry and the co-location of project team. Instead, temporal separation could be an effective mechanism of separation. Creating the appropriate project context could facilitate project ambidexterity. Extant studies on ambidexterity focus on the organizational level which may not apply at project level. This study examines the effects of the above three antecedents to project ambidexterity. The key findings are that ambidexterity can be achieved during the limited lifespan of a complex engineering project through: (1) partitioning the two approaches in different project phases and then integrating the two; (2) implementing policies and financial support aiming at facilitating contextual ambidexterity both at and above project level.