Yahoo! is a great proving ground for Agile. Since the introduction of Agile methods and practices into the company over five years ago, many contests of the Agile process have played out across the expansive Yahoo! software development landscape. Throughout its history, the spirit of Agile has survived, often in surprising and unexpected ways. Whether being mandated from the executive-level or arising from self-motivated small teams, one theme is constant - Agile has embedded itself into the DNA of Yahoo!. And to the present day, Agile continues to emerge and re-emerge in many forms from the dedicated individuals who use the tools of Agile to create some of the most innovative user experiences on the Internet. This paper offers an informal retrospective of the relative successes and failures of enterprise Agile adoption at Yahoo! from the period 2004 to 2009.