A System Security Plan (SSP) is a comprehensive document that details how an organization implements security controls and requirements for its information systems. The SSP describes the system’s boundaries, operational environment, hardware, software, and the specific security measures in place to protect data and maintain compliance with relevant regulations. It also outlines roles, responsibilities, and procedures for managing security risks and responding to incidents. SSPs are essential for demonstrating due diligence to auditors, regulators, and stakeholders, and are often required for government and regulated industry contracts. Regular updates ensure the plan remains effective as systems and threats evolve.