The Open Knowledge Initiative (O.K.I.) develops and promotes specifications that describe how the components of a software environment communicate with each other and with other enterprise systems. O.K.I. specifications enable sustainable interoperability and integration by defining standards for Service Oriented Architecture (SOA). Through this work O.K.I. seeks to open new market opportunities across a wide range of software application domains.

The O.K.I. project was initially launched in 2001 through a generous grant from the Andrew W. Mellon Foundation, and in collaboration with a number of like minded organizations.  Today the O.K.I. Phase II project is housed at the Office of Educational Innovation and Technology, a part of MIT's Dean of Undergraduate Education Office. 

The O.K.I. project has developed and published the Open Service Interface Definitions (OSID ?s), whose design has been informed by a broad architectural view. The OSIDs define important components of a SOA as they provide general software contracts between service consumers and service providers. This enables applications to be constructed independently of any particular service environment, and eases integration. The OSIDs enable choice of end-user tools by providing plugin interoperability.

OSIDs are software contracts only and therefore are compatible with most other technologies and specifications, such a SOAP, WSDL. They can be used with existing technology, open source or vended solutions.

OSIDs are a local language service definition and bindings of them are provided in Java and PHP, and investigatory work has been done with bindings for Objective C and C#.