Funding for federal programs that is provided through the annual appropriations process in regular appropriations acts is typically available for obligation during a single fiscal year, unless otherwise specified. This period of availability most often begins on the first day of the fiscal year of the appropriations act (October 1), also referred to as the "budget year." For example, appropriations provided by the FY2007 Department of Defense Appropriations Act ( P.L. 109-289 ), which was enacted on September 29, 2006, were generally available for obligation and expenditure on October 1, 2006, the first day of FY2007, and remained available through September 30, 2007. However, a delayed period of availability that begins after the start of the fiscal year, or even during a future fiscal year, may be provided for particular programs that are funded through the annual appropriations process. Delayed periods of availability are typically provided to meet specific budgetary needs related to the purpose or structure of a program. Some of the reasons to provide such periods of availability may be more broadly applicable, such as to prevent a funding shortfall late in the fiscal year or a funding gap in the following fiscal year. Although only a comparatively small number of individual programs receive funds that are available during such periods, many of these programs have a large number of beneficiaries. For example, portions of the Medicaid program, the Veterans Health Administration (VHA), and Department of Education formula grants are funded for delayed periods of availability. The statutory authority for a particular delayed period of availability may derive from provisions authorizing a particular program, those that provide appropriations to fund it, or a combination of the two. Under congressional rules, a statutory authorization of such a period of availability must precede an appropriation for those purposes. A program's authorizing statute may specifically address such a period of availability in the authorization of appropriations or address it more generally in the provisions that govern the program. If the authorizing statute itself does not suggest a delayed schedule for the funds, the legislative history associated with that statute could anticipate that such funds will be provided. Another possibility is that Congress could decide to use a delayed period of availability during the annual appropriations process even if the program's authorization or associated legislative history is silent as to timing of future funds or only authorizes a schedule that is aligned with the budget year. On the other hand, even when the authorization anticipates that funds will be available for a delayed period, appropriations may subsequently be provided on a schedule that is aligned with the budget year. In either instance, the period of availability associated with the appropriations would be controlling. A variety of approaches have been used during the annual appropriations process to provide funds that become available at some point after the beginning of the fiscal year. These include, but are not limited to, the three periods of availability: "advance appropriations," "forward funding," and "advance funding." Advance appropriations become available for obligation starting at least one fiscal year after the budget year. Forward funding becomes available beginning late in the budget year and is carried into at least one following fiscal year. A dvance funding is funding for the following fiscal year that becomes available for obligation late in the budget year and would be in addition to the funds for that fiscal year. Any expenditure of advance funds is counted as part of the following fiscal year's appropriation. These particular periods of availability as compared to annual appropriations are illustrated in Figure 1 . While these three delayed periods of availability all share some similarities, they are distinct concepts in three regards due to the timing of the funds. First, advance appropriations become available after the end of the budget year, whereas forward funds become available during the budget year. Second, advance appropriations become available at some point after the budget year has ended, whereas advance funds are available only during the budget year. Third, forward funds are available into the following fiscal year, whereas advance funds expire once the budget year ends. Although advance appropriations, forward funding, and advance funding are each discrete concepts, they tend to have some degree of variation in how they are implemented, including the interval in advance for which funds are provided and the duration of availability for those funds. For example, advance appropriations may be provided one or two fiscal years prior to when they become available for obligation and be available during a single fiscal year or multiple fiscal years or with no fiscal year limitation. In addition, a program may receive funds on a combination of timetables. Providing funds for a delayed period of availability may have budget process implications for Congress. Funds provided for such periods are generally subject to both procedural and statutory budget enforcement, and their budgetary effects are attributed (or "scored") to particular fiscal years for such purposes. Since FY2001, the budget resolution has also imposed limits for the House and Senate on advance appropriations for discretionary spending. For FY2014, these limits were established through the enactment of the Bipartisan Budget Act (Division A, H.J.Res. 59 ). As was previously mentioned, congressional rules require a statutory authorization that allows a delayed period of availability to precede an appropriation for those purposes. If a delayed period of availability for a program is not authorized by existing law, providing funding in a general appropriations bill or amendment thereto for such a period may subject that bill or amendment to a point of order. This report examines concepts, practices, and procedural implications associated with the particular delayed periods of availability described above. The following three sections discuss the origins, relevant budgetary concepts, and practices associated with advance appropriations, forward funding, and advance funding. The fourth section explains the budget process implications that are associated with these funding approaches. The scope of this report is generally restricted to an analysis of advance appropriations, forward funding, and advance funding in the context of the budget process. The program-specific considerations and potential consequences of these funding approaches are not discussed. For information on particular programs, see the CRS reports on those issue areas. Advance appropriations is a form of budget authority that becomes available one or more fiscal years after the budget year covered by the appropriations act. For example, in an appropriations act for FY2016, funds would generally become available for obligation on October 1, 2015. Advance appropriations in the FY2016 act would not become available until the start of FY2017 or later. According to the Congressional Budget Office (CBO), advance appropriations were first provided in 1962 for grants-in-aid that funded airport construction. Other early uses included grants for urban renewal and the Department of Education. Currently, this period of availability is used for a wide variety of programs funded by discretionary and appropriated mandatory spending. Perhaps the most significant implication of advance appropriations relates to funding gaps. The congressional budget process currently requires that annual appropriations be enacted by the beginning of the fiscal year (October 1). If such appropriations are not enacted by that time, one or more continuing resolutions (CRs) may be enacted to prevent a funding gap from occurring until regular appropriations are completed or the fiscal year ends. Programs that are funded through the appropriations process are at risk of a funding gap at the beginning of the fiscal year if annual appropriations or a CR is not enacted or at any point during the fiscal year when a CR expires and has not been replaced by a further CR or annual appropriations. However, if a program's appropriations for all or part of a fiscal year are enacted in the previous year's appropriations act, the program might not experience a funding gap, assuming that such appropriations were available during that period and were unexpended. A related implication, but one that is more generally associated with a program's annual operations, is that advance appropriations may enable that program to avoid the need for any continuing appropriations during periods when the regular appropriations bills for that fiscal year have not yet been enacted. The potential consequences of CRs on program operations have been noted by a variety of observers, including funding levels, program delivery, management support, and revenue collection. The extent to which a program has previously been provided advance appropriations that are available at the start of a fiscal year, that program would not be reliant on funding that would otherwise be provided through a CR. Some have argued that programs that receive advance appropriations may be better able to engage in advance planning. Enacting funding for a program in advance may enable it to make long-term commitments related to its internal operations or the population that it serves. Similarly, advance appropriations may assist agencies in planning and carrying out multi-year capital expenditures by spreading the cost over a number of fiscal years. However, others argue that the ability to make such commitments may be limited by the extent to which programmatic needs can be forecasted in advance. Congress may also prefer to exercise control over programs through regular annual appropriations in certain circumstances. Advance appropriations are typically enacted at an interval of one fiscal year prior to when such appropriations become available. For example, FY2013 funds for the "medical facilities" (VHA—Department of Veterans Affairs) account were provided one year in advance in the FY2012 appropriations act: For necessary expenses for the maintenance and operation of hospitals, nursing homes, domiciliary facilities, and other necessary facilities of the Veterans Health Administration; for administrative expenses in support of planning, design, project management, real property acquisition and disposition, construction, and renovation of any facility under the jurisdiction or for the use of the Department; for oversight, engineering, and architectural activities not charged to project costs; for repairing, altering, improving, or providing facilities in the several hospitals and homes under the jurisdiction of the Department, not otherwise provided for, either by contract or by the hire of temporary employees and purchase of materials; for leases of facilities; and for laundry services, $5,441,000,000 , plus reimbursements, shall become available on October 1, 2012, and shall remain available until September 30, 2013 .