Which NIST SP 800 series document is concerned with continuous monitoring of Federal Information Systems & organizations? Response:

NIST SP 800-137, titled 'Information Security Continuous Monitoring (ISCM) for Federal Information Systems and Organizations', provides comprehensive guidance on developing and implementing an ISCM program. This document details the processes for maintaining ongoing awareness of the information security and privacy posture of systems and organizations, which is crucial for effective risk management. It specifically addresses how to continuously monitor security controls and the effectiveness of an organization's security program.

NIST SP 800-26 focuses on security self-assessment guides, which is not primarily concerned with continuous monitoring.

NIST SP 800-64 provides guidance on security considerations within the system development life cycle (SDLC), not continuous monitoring.

NIST SP 800-144 offers guidelines on security and privacy in public cloud computing, which is a different area than continuous monitoring of federal systems.