For the past two decades, Michael Porter's work has towered over the field of competitive strategy. On Competition, Updated and Expanded Edition is a collection of Porter's landmark articles from the Harvard Business Review, capturing his unique ability to bridge theory and practice. Each of the articles has not only shaped thinking, but also redefined the work of practitioners in its respective field. In an insightful new introduction, Porter relates each article to the whole of his thinking about competition and value creation, and traces how that thinking has deepened over time.