Comprehensive overview of using Test Driven Development (TDD), Behavior Driven Development (BDD), Continuous Integration (CI), Continuous Delivery (CD), Development Operations (DevOps), and Development Operations Security (DevOpsSec). Describes the current global environment, basic lean and agile principles, and the evolution of Microservices. From there, a detailed deep-dive of TDD, BDD, CI, CD, DevOps, and DevOpsSec principles and practices ensues. Closes by identifying key DevOps tool automation ecosystems/pipelines, metrics, case studies, return on investment (ROI)/business cases, implementation roadmaps, adoption statistics, leadership insights, and a summary. Contains a lot of helpful data for constructing DevOps strategic business cases as well as tactical implementation strategies (while not ignoring essential elements such as microservices, containerization, and application security).