Individual Tax Identification Number, or ITINs, allow workers without a valid SSN to (1) report their earnings to the Internal Revenue Service (IRS) and to (2) open interest-bearing bank accounts. Without an ITIN, immigrant workers would not be able to file an income tax return. However, ITINs are in some cases being used to hurt rather than help immigrants. Due to this, the IRS is taking steps to curb ITIN use for purposes other than the filing of income tax returns. This handbook will guide users through the current ITIN application process. It will also examine the IRS ITIN program, including past, current and future concerns.