The Open Group is pleased, in association with the IEEE, to announce availability of the core volumes of Version 3 of the Single UNIX Specification on the World Wide Web. These volumes are also IEEE Std 1003.1 and ISO/IEC 9945. We request that you register your details in order to proceed to view or download the complete online version of the specification. Once registered you can then bookmark the table of contents page to avoid having to register again.