The National Science Foundation Act of 1950 directs the Foundation "to initiate and support basic scientific research and programs to strengthen scientific research potential and science education programs at all levels." NSF achieves its unique mission by making merit-based awards to researchers, educators, and students at approximately 1,700 U.S. colleges, universities and other institutions. In Fiscal Year (FY) 2005, NSF awards directly involved an estimated 195,000 people, including senior researchers, post-doctoral associates, and teachers, and students from kindergarten through graduate school. This report provides summary information about proposal and award activity and the process by which proposals are reviewed and awarded. (Contains 31 footnotes, 12 figures, 15 appendix tables, and a list of terms and acronyms.)