In an increasingly open environment of interconnected computer systems and networks, security is essential to ensure that information remains confidential, is not modified or destroyed and is available when needed. To help federal agencies protect sensitive, but unclassified information, the National Institute of Standards and Technology (NIST) has updated a set of guidelines for selecting and implementing cryptographic methods. Originally published in 1999, Guideline for Implementing Cryptography in the Federal Government (NIST Special Publication 800-21-1) is intended primarily for federal employees who design computer systems and procure, install and operate security products to meet specific needs. The publication is one of a series of key standards and guidelines produced by NIST’s computer security experts to help federal agencies improve their information technology security and comply with the Federal Information Security Management Act (FISMA) of 2002. FISMA requires all federal agencies to develop, document and implement agency-wide information security programs and to provide security for the information and information systems that support the operations and assets of the agency. The act called upon NIST to develop the standards and guidelines needed for FISMA compliance. The publication is available at its Web site.