use and access. Subsequent orders provided clarifications, standards and protocols. FERC Order 2000 Where as Order No. 888 provided for an entity (an ISO) to facilitate open access, it was not written with the intent to establish one. FERC Order No. 2000 was: Issued by the FERC on December 29, 1999, Order No. 2000 codified what it means to be an RTO including its minimum characteristics, functions and ratemaking policy. The order also stated its commitment toward open architecture with a stated goal that an RTO "...be designed so that they can evolve over time." The order still, however, does not mandate that a new entity called an RTO be created, nor does it mandate that an entity call itself an RTO to comply with the FERC's order. Independent system operators (ISOs) An ISO is an organization formed at the direction or recommendation of the Federal Energy Regulatory Commission (FERC). In the areas where an ISO is established, it coordinates, controls and monitors the operation of the electrical power system, usually within a single US State, but sometimes encompassing multiple states. Similar to an RTO, the primary difference is that ISOs either do not meet the minimum requirements specified by FERC to hold the designation of RTO or that the ISO has not petitioned FERC for the status. Electric utilities that are located within the United States and engage in interstate commerce fall under FERC authority. Not all utilities are members of ISOs. All utilities and ISOs, however, are responsible to meet the compliance of a larger organization called the North American Electric Reliability Corporation (NERC) which overlays the entire FERC footprint and also includes a Mexican utility and several Canadian utilities. As such, international reciprocity is commonplace, and rules or recommendations introduced by FERC often are voluntarily accepted by NERC members outside of FERC's jurisdiction. Therefore, one Canadian Province is a member of a US-based RTO, while two others function as an Electric System Operator (ESO), an organization essentially equal to a US-based ISO. Within the United States one ISO, and its participating utilities, does not fall under FERC authority: The Electric Reliability Council of Texas (ERCOT). ERCOT does fall under the authority of NERC and operates a reliability function, separate from its market function, in order to comply with NERC requirements. ISOs act as a marketplace operator in wholesale power, resulting from FERC order No. 888. Most are