The document discusses how teams at The Economist online work incrementally and iteratively on the same codebase to improve the site, with releases every Tuesday. It focuses on the importance of having a definition of "Done" and explains that for their teams, a story is Done when it has been implemented, verified through manual testing, validated by the product owner, and ready to be released to production. Defining and achieving Done increases productivity and allows for early delivery of business value and feedback. The teams use tools like Bazaar, Launchpad, Hudson and EC2 to manage their workflow, do peer reviews, and set up test instances for user stories.