History and mission
The NSF was established by the National Science Foundation Act of 1950. The stated mission of the NSF is
In this day and age, the NSF is less concerned with national defense, and more concerned with the previous two items.
- "To promote the progress of science; to advance the national health, prosperity, and welfare; and to secure the national defense."
The NSF attempts to promote various special programs, at times to help increase the participation in science of under represented minorities. For example, the Research Experience for Undergraduates (REU) program provides grants to research institutions for the purpose of providing undergraduate students the opportunity to perform research for a summer. This program targets women and minorities at many of the participant universities. The GK-12 Crosscutting Program provides money to universities with graduate students for the purpose of having graduate students interact with K-12 students. The goal is to increase student retention in the sciences starting at an early age. Other interdisciplinary programs unite various subfields of science, or the NSF and other funding agencies. And at this time all NSF grants carry with them a mandate to perform some form of outreach.
While a well established institution, the NSF has had some small controversies surrounding it.
The NSF and Antarctic cooling
For example, global warming theory states that the poles should warm faster than the rest of the earth, but researchers associated with the NSF discovered that just the opposite is happening:
But the methodology used in the study has been challenged 
- Researchers with the National Science Foundation (NSF) Long-term Ecological Research (LTER) site in Antarctica's Dry Valleys - a perpetually snow-free, mountainous area adjacent to McMurdo Sound - argue in the paper that long-term data from weather stations across the continent, coupled with a separate set of measurements from the Dry Valleys, confirm each other and corroborate the continental cooling trend. "Our 14-year continuous weather station record from the shore of Lake Hoare reveals that seasonally averaged surface air temperature has decreased by 0.7 degrees Celsius per decade," they write. "The temperature decrease is most pronounced in summer and autumn. Continental cooling, especially the seasonality of cooling, poses challenges to models of climate and ecosystem change." 
The NSF and NASA
In the current (and past) age of space exploration and astronomical study, it is often unclear what aspects of these fields should be handled (and funded) by the NSF, and what aspects should be in the realm of the National Aeronautics and Space Agency (NASA). Although both agencies want to increase our knowledge of space, the universe, and the human body, neither wants to pay more than it has to for these. At this point in time, an uneasy truce has developed, with NASA paying for space-based operations such as the Hubble Space Telescope (HST), Chandra (an X-ray satellite telescope), and the Space InfraRed Telescope Facility (SIRTF, to be renamed after successful completion of diagnostic tests, mid-December, 2003), and the NSF paying for ground-based operations such as the Atacomba Large Millimeter Array (ALMA, run by the National Radio Astronomy Observatory, NRAO), and Kitt Peak (located near Tucson, AZ).
Like all government sponsored organizations, the NSF has been accused of perpetuating conspiracies, such as suppressing UFO and crop circle information. However, perhaps due to the NSF's comparatively unknown existence to the American public, the sister organization of NASA receives much more bad press.