The numerator is calculated by summing of the number of facilities reporting availability of ART services. Information on the availability of specific services is usually kept at the national or sub-national level. National AIDS Programmes should have a record of all health facilities offering ART services. A health facility census or survey can also provide this information, along with more in-depth information on available services, provided the information is collected from a representative sample of health facilities in the country. Responses to a series of questions establish whether providers in that facility provide ART services directly (i.e., prescribe ART and/or provide clinical follow-up for ART patients) or refer patients to other health facilities for these services. In addition, facility records documenting the current status of service provision should be consulted. One potential limitation to facility surveys or censuses is that they are usually only conducted once every few years. Countries should regularly update their programme records on health facilities offering ART services, and supplement these data with those obtained through a health facility survey or census every few years. For health facility surveys or censuses, tools such as the Service Provision Assessment (SPA) or the Service Availability Mapping (SAM) can be used. Data Quality Control and Notes for the Reporting Tool • Please comment on whether the data reported is from a national facility listing or census, or from a survey. If data from the private or other sectors is missing, please comment. If it is possible to easily report any additional information on the geographical distribution of facilities offering ART (e.g. urban/rural, %facilities with ART in areas with a high concentration of PLWA), please provide extra details.