Last summer, Microsoft made a $1.2B investment in Yammer, recognizing enterprise social as key to how companies communicate and collaborate. Fast forward only eight months, and the momentum is tremendous. We've just finished our third quarter and Yammer sales grew 259% year-over year, Yammer gained 312 new customers, and March marked Yammer's best month to-date in terms of user engagement.
Taking enterprise social to the next level
While we are pleased with the growth, the opportunity for enterprise social is even larger. Yammer and Microsoft have come together with a single vision - to bring enterprise social to all businesses by weaving these capabilities into the apps people use every day. Realizing this vision requires close alignment in product development, sales and marketing.
On the engineering side, we've made great strides in a short timeframe, bringing together Yammer and Office 365 teams to deliver regular updates against our roadmap. Right now our teams are actively focused on foundational work around identity, content and messaging that will drive seamless connected experiences across Office 365 and other applications. We look forward to sharing more exciting developments soon.
The next area of focus is aligning the Yammer and Office 365 go-to-market efforts. On March 1, we began offering Office 365 and Yammer together as part of Enterprise Agreements. We will further simplify the customer buying experience and increase global scale by fully integrating our sales teams this summer. We're going from about a hundred sellers at Yammer to several thousand Microsoft sellers around the world bringing customers the benefits of enterprise social.
We continue to invest aggressively in the Yammer business and are hiring in sales, engineering, customer engagement and marketing this year.
Customer momentum
The reaction from customers has been overwhelmingly positive. They are excited about the transformational potential of enterprise social and recognize the combined value of Office 365 and Yammer. Just one example we recently announced is ABB, a power and automation technology leader using Office 365 and Yammer to provide a single platform for productivity, communication, collaboration and enterprise social in the cloud for 145,000 employees across 100 countries.
We're just getting started
This is an exciting time for Microsoft and our customers as we pioneer the next generation of collaboration services for the workplace. We're excited about the value customers are seeing with Office 365 and Yammer together, and we believe this is just the beginning. Curious about enterprise social and the impact it can have on your business? Check out the Social Journey, a step-by-step guide on driving success using enterprise social or learn more about how leading companies are using Yammer.