Business strategy is a relatively new phenomenon, though people have informally been drafting and implementing strategies of various kinds for thousands of years. In this chapter, the dominant schools of business strategy are introduced and briefly critiqued in terms of strengths, weaknesses, and major contribution to the field. Also discussed are the criteria necessary for a good strategy as well as how strategy relates to marketing and sales. Most important is the section on the challenges of strategy and execution with an emphasis on implementation, which has been noted as the weakest and least developed content area of successful business strategy. The chapter closes with some observations on how the Theory of Constraints helps fill critical gaps in knowledge of business strategy with a particular emphasis on the TOC contribution to implementation.