At Facebook, our mission is clear. Give people the power to share and make the world more open and connected. Over 13,000 Facebook employees wake up committed to making this mission a reality for the more than 1 billion people who use Facebook every day.

Our mission is enabled by our company culture and together, they shape how we work together. The IT organization at Facebook is focused on having the most productive workforce possible and the foundation for Facebook’s continual innovation is our ethic of collaboration that empowers everyone to bring their best ideas to the table. To enable our productivity, IT at Facebook provides our people with the best tools available. Tools that can mean the difference between just having an idea and bringing that idea to life.

The people who use Facebook are distributed around the world, and to support them, our people are globally distributed as well. We facilitate their productivity by letting them choose the device and platform that is most effective for them. We collaborate on everything online—no files, no fragmented information stores—and we provide our employees with the ability to work anywhere and in any way they want.

All of this means that our IT has to be flexible and available over the web, on mobile and across platforms—wherever our employees need it. Enabling this mobility requires a secure environment that defends against cyber attacks and protects mobile devices, especially if a device gets stolen or hacked.

My team is responsible for balancing these often competing pressures. Productivity is our most important charter, but security and efficiency are also paramount. We need the right technology to empower employees, while also ensuring our business is safe at all times.

This is why we’ve implemented Office 365. Not only is it a mature and comprehensive platform, it meets our stringent security standards, it complements how we work with intelligence, flexibility, and it is continually evolving. It is globally deployed, accessible on every mobile platform we support, and it is secure. Most of all, it enables our productivity with powerful new capabilities for employees, such as the ability to share and edit traditional Excel documents at the same time, across devices.

Office 365 also brings capabilities beyond Word, Excel and PowerPoint that are hard to replicate. Delve, using the Microsoft Graph, brings a new level of intelligence to collaboration by offering additional insights on how our employees work with each other. It tells individuals who they are collaborating with the most, and how much time is being spent where. These personal analytics, and other features like Focused Inbox, help create greater effectiveness at work. We’re also very excited about how we can leverage the Microsoft Graph within our own internal Facebook tools and services. This will help our employees sift through the noise by surfacing the information that is most relevant for them.

As Microsoft continues to innovate with Office 365, we will continue adding and rolling out more services that have value for Facebook. In that way, we’re not just buying the capabilities that Office 365 offers today. We are also buying capabilities that Microsoft will offer over time, and expect even greater things to come.

Source: Why Facebook is betting on Office 365 and the Microsoft Cloud - Office Blogs