This web site describes the CardDAV protocol, and includes details about the protocol, related standards, CardDAV products and other related information. It is kindly being hosted by The Calendaring and Scheduling Consortium.

CardDAV is an address book client/server protocol designed to allow users to access and share contact data on a server.

The CardDAV protocol is being developed by the IETF and is currently an internet draft.

Several vendors have announced support for CardDAV.