Enterprises engaged in mission-critical computing, either on commodity or proprietary hardware, are choosing open-source Linux in increasing numbers. In this guide, I look at a number of factors driving adoption of Linux in the enterprise, including uptime, performance, high availability, administration and other drivers. In the context of what matters most in the enterprise, I discuss why Linux is the best choice in the enterprise and consider how SUSE has positioned its SUSE Linux Enterprise Server to serve the needs of the most demanding IT organizations.