Exchange Online delivers Message Encryption to EnterPrise Customers, and also for Business Customers mixing Azure Rights Management with Business Plans.
I am looking forward to using Enterprise Mobility Suite with Business customers aswell, which is announced to be available on Open Agreement in December.
Until now the receiver had to have a Organizational Account or Microsoft Account to be able to decrypt and read the encrypted Messages from Exchange Online Users, but now Microsoft has introduced the One-Time Passcode feature for Message Encryption aswell.
The One-Time Passcode will be included in the email with the link directing you to Exchange Online Web Access.
Source: Office Blog.
Later this week I’ll make a blogpost about what Administrators need to configure before Message Encryption will work for the end users.