TDD is promoted as a powerful technique for combining software design, testing, and coding to increase reliability and productivity. However the transition to TDD is not always easy. Is it worth the effort and what can really be gained from it? This report describes a useful transition strategy based on different TDD styles and identifies key elements required for each style. It identifies differences found on code that developed using these TDD styles. The differences are striking in their consistency and give a strong indication that TDD is well worth the effort.