Commerce Server is a software product for building multichannel e-commerce applications and systems using Microsoft .NET technology.The product has changed ownership and names several times. Previously known as Microsoft Commerce Server, it is now developed, sold, and supported by Sitecore; although Microsoft will honor extended support of Microsoft Commerce Server 2009 through 2019. The latest release of the product is Sitecore Commerce Server 11.1, released in October 2014.