The Financial Accounting Standards Board (FASB) is one of three organizations primarily in charge of setting U.S. GAAP (Generally Accepted Accounting Principles). The other two are the Securities and Exchange Commission (SEC) and the American Institute of Certified Public Accountants (AICPA).
Before you get into the meat and potatoes of FASB, you need a little history lesson! Resulting from some congressional criticism of the standard-setting work being done by the AICPA, the Financial Accounting Foundation (FAF) was established in the state of Delaware as a nonprofit corporation.
The FAF, in turn, established the Financial Accounting Standards Board (FASB), which, ta-da!, is currently the private-sector body establishing GAAP for all nongovernmental entities.
Governmental entities follow procedures set up by the Governmental Accounting Standards Board (GASB).
The FASB has five full-time members, who are selected by the FAF. All are required to have knowledge of accounting, finance, and business. For more info on the FASB, accounting standards, and FAF, check out the FASB website.
The FASB further formed the Emerging Issues Task Force (EITF) in 1984 to help identify emerging accounting issues in need of standardization. The EITF consists of accounting professionals who meet six times a year with nonvoting members of the SEC and FASB to mull over current economic, business, and industrial developments.