This study explores the meaning project managers (PMs) make of their project environment, how they lead their teams and have incorporate complexity into their project management approach. The exploration of the PM's developmental level and meaning making offers a different angle on the project management and leadership literature. The study expands from the traditional project management leadership literature and provides an alternative lens to the conversation. This expansion incorporates the subjective, interpretive, construct oriented side of leadership and explores "how" the PM knows instead of "what" the PM knows (Eigel, 1998). This study pulls together two streams of neo-Piaget developmental theory. The first stream is focused on cognitive development and hierarchical complexity and the individual's ability to construct and coordinate increasingly complex concepts by theorists such as Michael Commons, Theo Dawson, and Kurt Fischer. The second stream of constructive developmental theory concentrates on individual meaning-making and the process of differentiation and integration of the subjective and objective experiences as discussed by theorists such as Susanne Cook-Greuter, Robert Kegan, and Bill Torbert. Participants were assessed for their developmental level using the Lectical(TM) Assessment System's (LAS) Lectical(TM) Decision Making Assessment (LDMA). This study has significant implications for the fields of leadership, project management, and constructive developmentalism. The overall finding of this study is way the PM leads the project team. Each of the three Achiever level groupings had distinct approaches to how the PM structured and approached the project team. This influence affected how the PM approached complexity to how the PM integrated the larger organization into the project. A constructive developmental lens has provided important insight for project management leadership practice as well as theory. It is recommended that project management theorists and practitioners consider the meaning making of the PMs to better understand approaches to project management and project success and failure. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]