The tasks of ICANN include responsibility for Internet Protocol (IP) address space allocation, protocol identifier assignment, generic (gTLD) and country code Top Level Domain name system management, and root server system management functions. More generically, ICANN is responsible for managing the assignment of domain names and IP addresses. To date, much of its work has concerned the introduction of new generic top-level domains. The technical work of ICANN is referred to as the IANA function. ICANN's other primary function involves helping preserve the operational stability of the Internet; to promote competition; to achieve broad representation of global Internet community; and to develop policies appropriate to its mission through bottom-up, consensus-based processes.

On September 29, 2006, ICANN signed a new agreement with the United States Department of Commerce (DOC) that is a step forward toward the full management of the Internet's system of centrally coordinated identifiers through the multi-stakeholder model of consultation that ICANN represents.

Paul Twomey has been the President/CEO of ICANN since March 27 2003. As of November 3, 2007, Peter Dengate Thrush replaced Vint Cerf as Chairman of the ICANN Board of Directors .

Structure

At present, ICANN is formally organized as a non-profit corporation "for charitable and public purposes" under the California Nonprofit Public Benefit Corporation Law. It is managed by a Board of Directors, which is composed of six representatives of the Supporting Organizations, sub-groups that deal with specific sections of the policies under ICANN's purview; eight independent representatives of the general public interest, selected through a Nominating Committee in which all the constituencies of ICANN are represented; and the President and CEO, appointed by the rest of the Board.

There are currently three Supporting Organizations. The Generic Names Supporting Organization (GNSO) deals with policy making on generic top-level domains (gTLDs). The Country Code Names Supporting Organization (ccNSO) deals with policy making on country-code top-level domains (ccTLDs). The Address Supporting Organization (ASO) deals with policy making on IP addresses.

ICANN also relies on some advisory committees to receive advice on the interests and needs of stakeholders that do not directly participate in the Supporting Organizations. These include the Governmental Advisory Committee (GAC), which is composed of representatives of a large number of national governments from all the world; the At-Large Advisory Committee (ALAC) which is composed of representatives of organizations of individual Internet users from around the world; the Root Server System Advisory Committee which provides advice on the operation of the DNS root server system; the Security and Stability Advisory Committee (SSAC) which is composed of Internet experts who study security issues pertaining to ICANN's mandate; and the Technical Liaison Group (TLG) which is composed of representatives of other international technical organizations that focus, at least in part, on the Internet.