Windows 8.1 Pro

Windows 8.1 Pro is the operating system intended for small and medium-sized businesses. It provides abilities such as joining corporate domains, participating in Group Policy, allowing involvement in Work Place Join and Work Folders, encryption and more.

Product key and instructions are sent immediately via email after purchase for this product.

You can find a good list of business features in the The IT Guide to Windows 8.1. Note that some of the new business features in Windows 8.1 Pro require a server running Windows Server 2012 R2 somewhere in the organization.