Our success at Cisco has been defined by how we anticipate, capture, and lead through market transitions. Over the years, I’ve watched iconic companies disappear—Compaq, Sun Microsystems, Wang, Digital Equipment—as they failed to anticipate where the market was heading. Today we’re navigating several fundamental technology transitions, including cloud computing, mobility, and the internet of everything. These transitions force us and our customers to think about data, security, and business models differently. That means making tough decisions and immersing ourselves in a process of disrupting the market and at times ourselves. When you’re a large company with significant market share, it’s tempting to view market disruptions as a threat, but we view them as an opportunity. When a market isn’t in transition, gaining market share is hard—you’re fighting to take one or two points of share from competitors. That’s why we’re transforming our entire business, expanding to capture growth, and thinking very differently about the future of information technology.

A version of this article appeared in the May 2015 issue (pp.35–38) of Harvard Business Review.