W3C
The World Wide Web Consortium, or W3C, is responsible for the administration of many of the Internet message protocol specifications, such as HTML, XML, XML Schema, XSLT, and XPath. You can also find the SOAP working draft and the WSDL note at their site.
OASIS
The Organization for the Advancement of Structured Information Standards, or OASIS, is responsible for many e-business standards that fall outside the normal realm of the W3C. OASIS is currently responsible for the Universal Description, Discovery, and Interchange (or UDDI) specification, as well as the e-business XML (ebXML) specification set.
ISO
The International Organization for Standardization, or ISO, is a worldwide federation of standards bodies. Their mission is to promote the development of international standards across intellectual, scientific, technological and economic activities. They administer the ISO 11179 specification, which provides an ontology for the description of individual data points.