The National Science Foundation (NSF) supports both basic research and education in the non-medical sciences and engineering. Congress established the foundation through the National Science Foundation Act of 1950 to "promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense; and for other purposes." The NSF is a major source of federal support for U.S. university research, especially in certain fields such as mathematics. It is also responsible for significant shares of the federal science, technology, engineering, and mathematics (STEM) education program portfolio and federal STEM student aid and support. This report describes selected items from the Obama Administration's FY2017 budget request for NSF and tracks legislative action on FY2017 appropriations to the foundation. It also details selected authorizations of NSF appropriations proposed in the 114 th Congress, summarizes budget and appropriations action from FY2015 and FY2016, and presents information on historical funding for the foundation. NSF has six major appropriations accounts: Research and Related Activities (RRA), Education and Human Resources (EHR), Major Research Equipment and Facilities Construction (MREFC), Agency Operations and Award Management (AOAM), National Science Board (NSB), and the Office of the Inspector General (OIG). At times, authorizations and appropriations have been specified at the RRA subaccount level, and NSF's budget justifications detail activities and obligations at that level. The majority of NSF's primary mission activities are funded through RRA, EHR, and MREFC. NSF adopted its current appropriations account structure in FY2003. In general, NSF's major accounts have been comparable since then. Appropriations to NSF are typically included in annual Commerce, Justice, Science and Related Agencies Appropriations Acts. (The Congressional Research Service tracks these acts on CRS.gov, at http://www.crs.gov/AppropriationsStatusTable/index .) NSF's budget justifications are published on the agency's website at http://www.nsf.gov/about/budget/ . The Obama Administration sought $7.964 billion for NSF in FY2017, a $501 million (6.7%) increase over the FY2016 estimate of $7.463 billion (see Table 1 ). This request included $7.564 billion in discretionary budget authority and $400 million in new one-time mandatory budget authority (excluding new mandatory funding, the total NSF request was $101 million (1.3%) greater than the FY2016 appropriation). The request would have increased budget authority in three accounts relative to the FY2016 estimate: RRA by $392 million (6.5%), EHR by $73 million (8.3%), and AOAM by $43 million (13%). The NSB and OIG accounts would have received about the same amount as in FY2016. Funding for the MREFC account would have decreased by $7 million (3.6%). The requested mandatory budget funding would have been split between two accounts—$346 million for RRA and $54 million for EHR. It is not typical for NSF to request or receive mandatory funding for major accounts. As reported by the Senate Committee on Appropriations on April 21, 2016, S. 2837 , the Commerce, Justice, Science, and Related Agencies Appropriations Act, 2017, would have provided a total of $7.510 billion to NSF for FY2017. This amount would have been $46 million (0.6%) above the FY2016 estimated funding level, $54 million (0.7%) below President Obama's FY2017 discretionary funding request, and $454 million (5.7%) below the request including new mandatory funding. This bill would have kept funding for each of the major accounts at nearly the same level as the FY2016 estimate, except for the MREFC account, which would have increased by $46 million (23%). As reported by the House Committee on Appropriations on June 6, 2016, H.R. 5393 , the Commerce, Justice, Science, and Related Agencies Appropriations Act, 2017, would have provided a total of $7.406 billion to NSF for FY2017. This amount would have been $57 million (0.8%) below the FY2016 estimated funding level, $158 million (2.1%) below President Obama's FY2017 discretionary funding request, and $558 million (7.5%) below the request including new mandatory funding. The bill would have kept funding for the EHR, NSB, and OIG accounts nearly the same as the FY2016 estimate, increased the RRA and AOAM accounts by $46 million (0.8%) and $10 million (3%), respectively, and decreased the MREFC account by $113 million (57%). The Consolidated Appropriations Act, 2017 ( P.L. 115-31 ), signed by the President on May 5, 2017, provides $7.472 billion in discretionary funding to NSF, 0.1% above the FY2016 enacted amount. The Further Continuing and Security Assistance Appropriations Act, 2017 ( P.L. 114-254 ), provided funding at about 99.8% of the FY2016 funding level for the NSF through April 28, 2017. The Continuing Appropriations and Military Construction, Veterans Affairs, and Related Agencies Appropriations Act, 2017 ( P.L. 114-223 ), provided funding for the NSF from October 1, 2016 through December 9, 2016, at the FY2016 funding rate subject to a 0.496% across-the-board decrease. The FY2017 NSF budget justification highlighted many of the same programs as in FY2016. Specifically, the document identified two areas of major emphasis, four cross-foundation investments, and six on-going NSF-wide priorities. The two areas of major emphasis—a new classification in the FY2017 budget document—are Clean Energy Research and Development (R&D) and strengthening support for core activities: The FY2017 request would have increased funding across multiple offices and RRA directorates for Clean Energy R&D by $141 million to $512 million total, a 37.9% increase. Clean Energy R&D appears to have broadly included Clean Energy Technology, listed as one of the cross-foundation investments in FY2016. Strengthening support for core activities would have been funded by the new mandatory budget authority request of $400 million to support "fundamental, curiosity-driven research," with a focus on supporting early-career investigators. The budget justification reported that the mandatory funding would have allowed for an estimated 800 additional research grants to be funded. The foundation's four cross-foundation investments aim to bring researchers from different fields of science and engineering together to address cross-disciplinary questions. As in FY2016, these activities included the following: Understanding the Brain (UtB, $142 million requested, 3.6% decrease from FY2016 estimate); Risk and Resilience ($43 million requested, 4.9% increase); Innovations at the Nexus of Food, Energy, and Water Systems (INFEWS, $62 million requested, 27.7% increase); and NSF Inclusion across the Nation of Communities of Learners of Underrepresented Discoverers in Engineering and Science (NSF INCLUDES, $16 million requested, 3.2% increase). NSF identified six ongoing foundation-wide priorities for FY2017. These included the following: Cyber-Enabled Materials, Manufacturing, and Smart Systems (CEMMSS, $257 million requested, 0.3% increase over the FY2016 estimate); Cyberinfrastructure Framework for 21 st Century Science, Engineering, and Education (CIF21, $100 million requested, 24.4% decrease); Innovation Corps (I-Corps, $30 million requested, no change); Research at the Interface of Biological, Mathematical, and Physical Sciences (BioMaPS, $30 million requested, 4.8% decrease); Science, Engineering, and Education for Sustainability (SEES, $52 million requested, 29.8% decrease); and Secure and Trustworthy Cyberspace (SaTC, $150 million requested, 15.4% increase). The NSF Research Traineeship (NRT) program was no longer included in the foundation-wide priorities list, though NRT was noted as a crosscutting program with funding from the RRA and EHR accounts. The overall FY2017 request for NRT was $58.6 million, an 8.3% increase from the FY2016 estimate (including a 9.4% decrease in requested funding through RRA and a 21.4% increase through EHR); this remained lower than the $74.4 million in enacted funding level for NRT in FY2015. For another widely tracked crosscutting program, the Graduate Research Fellowship (GRF), the FY2017 request was about the same as the FY2016 estimate ($332 million). The report to accompany S. 2837 , S.Rept. 114-239 (referred to as the "Senate report" in this section), specifically addressed one of these NSF-wide funding priorities, stating "The Committee supports the NSF's request for the Innovation Corps [I–Corps] program ..." The report to accompany H.R. 5393 , H.Rept. 114-605 (referred to as the "House report" in this section), recommended $5 million above the requested level for I-Corps "to enable greater participation nationally." The explanatory statement accompanying P.L. 115-31 directs NSF to provide the requested level of $30 million for I-Corps. Broadly, both reports expressed support for programs that focus on such things as cybersecurity and broadening participation in STEM fields from underrepresented populations. As reported, neither S. 2837 nor H.R. 5393 would have included the $400 million in new mandatory funding requested to strengthen support for core services.