Types of Information and Information Systems to Security Categories." The overall FIPS 199 system categorization is the "high water mark" for the impact rating of any of the criteria for information types resident in a system. For example, if one information type in the system has a rating of "Low" for "confidentiality," "integrity," and "availability," and another type has a rating of "Low" for "confidentiality" and "availability" but a rating of "Moderate" for "integrity," then the impact level for "integrity" also becomes "Moderate". Security controls Federal information systems must meet the minimum security requirements. These requirements are defined in the second mandatory security standard required by the FISMA legislation, FIPS 200 "Minimum Security Requirements for Federal Information and Information Systems". Organizations must meet the minimum security requirements by selecting the appropriate security controls and assurance requirements as described in NIST Special Publication 800-53, "Recommended Security Controls for Federal Information Systems". The process of selecting the appropriate security controls and assurance requirements for organizational information systems to achieve adequate security is a multifaceted, risk-based activity involving management and operational personnel within the organization. Agencies have flexibility in applying the baseline security controls in accordance with the tailoring guidance provided in Special Publication 800-53. This allows agencies to adjust the security controls to more closely fit their mission requirements and operational environments. The controls selected or planned must be documented in the System Security Plan. Risk assessment The combination of FIPS 200 and NIST Special Publication 800-53 requires a foundational level of security for all federal information and information systems. The agency's risk assessment validates the security control set and determines if any additional controls are needed to protect agency operations (including mission, functions, image, or reputation), agency assets, individuals, other organizations, or the Nation. The resulting set of security controls establishes a level of "security due diligence" for the federal agency and its contractors. A risk assessment starts by identifying potential threats and vulnerabilities and mapping implemented controls to individual vulnerabilities. One then determines risk by calculating the likelihood and impact that any given vulnerability could be exploited, taking into account existing controls. The culmination of the risk assessment shows the calculated risk for all vulnerabilities and describes whether the risk should be accepted or mitigated. If mitigated by the implementation of a control, one needs to describe what additional Security Controls will be added to the system. NIST also initiated