Senior Information Systems Security Representative (ISSR) – Technical Lead

Guidehouse • Washington, DC

2d • Onsite

About The Position

Our Cybersecurity Consultants are a team of business integrators with extensive consulting and industry experience who help our clients solve their complex business issues from strategy through execution. A career in an integrated team of developers and consultants provides the opportunity to grow and contribute to our clients' business issues every day, applying a collection of security spectrum capabilities, including security strategy and governance, IT risk, security technologies, and cybercrime and breach response. We are seeking a highly experienced Senior Information System Security Representative (ISSR) – to support a major federal mission. The Senior ISSR serves as a key security compliance lead responsible for ensuring controlled systems are authorized, operated, and maintained in accordance with federal policy, NIST guidance, and established Security Assessment and Authorization (SAA) requirements. This role works closely with system owners, ISSOs, ISSEs, assessors, and Authorizing Officials to ensure security documentation is accurate, risks are well understood, and systems maintain continuous compliance.

Requirements

• Bachelor’s degree in Cybersecurity, Information Systems, Computer Engineering, or related technical field.
• Minimum of TEN (10) years of professional IT or cybersecurity experience, including substantial senior‑level responsibilities.
• Minimum of SEVEN (7) years of direct ISSR or A&A/SAA experience supporting cleared federal environments.
• An ACTIVE and CURRENT TOP SECRET federal or DOD security clearance.
• Strong understanding of security frameworks and compliance standards (e.g., NIST, RMF SP 800-53 Rev 5, DoD 8570).
• Demonstrated leadership in RMF lifecycle execution, SAA/ATO process management, and security governance.
• In‑depth knowledge of NIST guidance, security authorization processes, and federal cybersecurity compliance frameworks.
• Proven ability to work with Authorizing Officials, senior stakeholders, and diverse technical teams.
• Strong analytical, documentation, communication, and mentoring skills.
• Demonstrated ability to lead cross-functional teams and complex technical projects.
• Strong analytical and problem-solving skills.
• Excellent communication skills with the ability to convey technical concepts to non-technical stakeholders.

Nice To Haves

• Master’s Degree in relevant cybersecurity or IT field
• One or more of the following certifications: ISC2 Zero Trust Strategy Certificate, Certified Information Security Manager (CISM), Certified Information Systems Security Professional (CISSP), Certified Authorization Professional (CAP) / Certified in Governance, Risk and Compliance (CGRC)
• Familiarity with ATO workflow systems used by federal law‑enforcement and national‑security agencies.
• Project Management Professional (PMP) or Scaled Agile Framework (SAFe) certification for managing cybersecurity projects in Agile environments.

Responsibilities

• Ensure controlled systems operate in accordance with approved SAA/ATO requirements and agency security policies.
• Lead and manage the SAA process for new systems, legacy systems onboarding, and systems migrating into the governance, risk, and compliance (GRC) platform.
• Guide system owners on baseline security controls, system categorization, impact levels, and authorization boundary definition.
• Provide recommendations to the Authorizing Official on classification decisions, boundary updates, and risk posture.
• Oversee creation and maintenance of system entries within the GRC tool, ensuring categorizations and metadata remain current.
• Initiate, coordinate, and recommend ISAs, MOUs, and MOAs required for interconnections between controlled systems and external partners.
• Conduct independent reviews of System Security Plans (SSPs), ensuring accuracy, completeness, and alignment with federal requirements.
• Determine appropriate assessment levels and coordinate testing activities with assessment teams and Authorizing Officials.
• Schedule and support security control assessments, inspections, and system reviews in partnership with system owners and assessors.
• Compile and submit complete SAA/ATO packages for executive authorization decisions.
• Track and ensure serialization of ATO documentation within agency tracking systems (e.g., Sentinel).
• Advise Authorizing Officials on vulnerabilities, residual risks, and recommended risk acceptance or remediation actions.
• Oversee POA&M management to ensure remediation actions are tracked, completed, and re‑tested.
• Coordinate event‑driven reauthorization activities when major system changes or incidents occur.
• Support the decommissioning and secure retirement of controlled systems in collaboration with ISSOs, ISSEs, and system owners.

Benefits

• Medical, Rx, Dental & Vision Insurance
• Personal and Family Sick Time & Company Paid Holidays
• Parental Leave
• 401(k) Retirement Plan
• Group Term Life and Travel Assistance
• Voluntary Life and AD&D Insurance
• Health Savings Account, Health Care & Dependent Care Flexible Spending Accounts
• Transit and Parking Commuter Benefits
• Short-Term & Long-Term Disability
• Tuition Reimbursement, Personal Development, Certifications & Learning Opportunities
• Employee Referral Program
• Corporate Sponsored Events & Community Outreach
• Care.com annual membership
• Employee Assistance Program
• Supplemental Benefits via Corestream (Critical Care, Hospital Indemnity, Accident Insurance, Legal Assistance and ID theft protection, etc.)
• Position may be eligible for a discretionary variable incentive bonus

What This Job Offers

• Job Type: Full-time
• Career Level: Senior