A year ago, we announced that you could use your Office 365 credentials to sign in to Yammer. Today we’re excited to share with you a new feature that supports enforcing Office 365 identity in Yammer. By enforcing Office 365 identity in Yammer and configuring federated identity in Office 365, admins can achieve single sign-on (SSO) capabilities for all services in Office 365, which includes Yammer. This further enables administrators to seamlessly manage Yammer from Office 365.
Check out more details as part of Office Blogs here