This is the fifth report from an evaluation of the Principal Pipeline Initiative (PPI), in which six large urban school districts have received support for strengthening novice principals' capabilities through specific strategies. Data for the evaluation were collected from late 2011 through spring 2015, using interviews with district administrators, surveys and focus groups of novice principals, and reviews of district documents. Details about study methods appear in the body of this report. This culminating report summarizes findings about implementation of the four PPI components across the six districts, as of spring 2015 when all components were expected to be up and running. The report details the implementation approaches, accomplishments, and challenges of participating districts; identifies factors that helped or impeded their progress; highlights lessons learned; and presents implications for policymakers and other districts. An evaluation report about the effects of the PPI on student achievement is scheduled for publication in 2018. This study of the initiative's implementation was designed to draw lessons about the process and early results of the work done in districts with varying histories in different states and regions. Intended audiences for the report include other school districts that might embark on similar approaches and policymakers who might support such efforts. The following are appended: (1) Survey Administration, Weighting, and Analyses; and (2) An Exploratory Comparative Analysis. [For Volume 1 in this series, see ED555867; for Volume 2, see ED555868; for Volume 3, see ED555869; and for Volume 4, see ED570471.]