This chapter illuminates the current theories and concepts concerning complexity and the project management workforce competencies necessary to deal with it in projects. It exposes the valuable, yet underutilised, opportunities complex projects may present to develop the knowledge and competencies of a workforce to successfully manage complexity within a project space and across an organisation more generally. The theoretical implications of this analysis imply that more research is necessary to establish a framework of competencies that relate appropriately to the levels of complexity within a project. The practice implications are profound since managing complexity in projects requires a more expansive and divergent set of practitioner skills that move well beyond the baseline 'technically oriented' project management skills set. In sum, this chapter highlights the current strengths and weaknesses of extant research and standards concerning complexity in projects and provokes discussion on developing a workforce that is more 'complexity' capable.