Alternate Lead Senior Information Systems Security Officer (ISSO)

Work Type: Hybrid — Washington, DC; on-site at least 2 days per week
Industry Category: Cybersecurity / Federal Information Security
Employment Type: Full-Time Contract — Key Personnel
Clearance Requirement: Must be eligible for and capable of obtaining a Tier 4 (High-Risk Public Trust) background investigation
Salary: $150,000–$200,000 per year as a W2, negotiable for the right candidate.
Citizenship Requirement: U.S. Citizenship Required

Position Overview

Our client is seeking an experienced Alternate Lead Senior Information Systems Security Officer (ISSO) to support a federal cybersecurity program. This full-time Key Personnel position will provide senior-level ISSO support and serve as the designated alternate to the Lead Senior ISSO.

The selected candidate must be able to assume Lead ISSO responsibilities during scheduled or unscheduled absences without service degradation while independently leading assigned RMF, continuous monitoring, vulnerability management, POA&M, and audit-support activities.

Key Responsibilities

• Perform senior ISSO responsibilities across assigned federal information systems.
• Serve as the designated alternate to the Lead Senior ISSO and assume Lead responsibilities when required.
• Lead assigned NIST RMF, system authorization, security control assessment, ATO/reauthorization, and ongoing monitoring activities.
• Develop, review, and maintain security authorization documentation and supporting evidence.
• Lead assigned ISCM/ConMon, security-posture reporting, vulnerability management, remediation, and POA&M activities.
• Support Security Impact Analyses (SIAs) and cybersecurity requirements associated with system and configuration changes.
• Support incident response, evidence collection, root-cause analysis, and corrective-action tracking.
• Support cybersecurity audits, assessments, FISMA reporting, compliance reviews, and audit readiness.
• Conduct quality reviews and maintain accurate, complete, and current cybersecurity documentation.
• Coordinate with the Lead ISSO, ISSM, System Owners, cybersecurity leadership, assessors, technical teams, and other stakeholders.

Minimum Qualifications

• U.S. citizenship required.
• Must be eligible for and capable of obtaining a Tier 4 (High-Risk Public Trust) background investigation.
• Senior-level experience as an ISSO or in a closely related federal cybersecurity role.
• Experience with NIST RMF, FISMA, system authorization, ATO/reauthorization, security control assessment, and continuous monitoring (ISCM/ConMon).
• Experience with vulnerability management, POA&M, remediation, cybersecurity audits, compliance, and audit readiness.
• Experience developing and maintaining federal cybersecurity documentation, including SSPs, POA&Ms, Continuous Monitoring Plans, SAP/SARs, SIAs, incident response and contingency plans, and security control evidence.
• Demonstrated ability to independently lead RMF, continuous monitoring, vulnerability management, POA&M, or audit-support workstreams.
• Ability to assume the Lead Senior ISSO role during scheduled or unscheduled absences and maintain operational continuity.
• Working knowledge of applicable NIST SP 800-series cybersecurity standards and guidance.
• Proficiency with ServiceNow, CSAM, Splunk, and vulnerability-scanning platforms.
• Familiarity with Tenable/Nessus or Qualys, Microsoft Defender, Intune, BigFix, Azure, Microsoft 365 security/compliance tools, Entra ID, Okta, Palo Alto Panorama, and Zscaler.
• Strong analytical, technical-writing, communication, coordination, and problem-solving skills.
• Ability to work on-site in Washington, DC at least two days per week, with additional on-site support as required.

Preferred Qualifications

• Relevant education and professional cybersecurity certifications.
• Prior experience as a Senior ISSO, Alternate Lead ISSO, Lead ISSO, or similar senior federal cybersecurity professional.
• Advanced hands-on experience with CSAM, Splunk, ServiceNow, and enterprise vulnerability-management platforms.
• Experience supporting multiple federal information systems through RMF authorization and continuous-monitoring lifecycles.
• Experience leading cybersecurity audits, vulnerability/POA&M remediation, continuous monitoring, or federal cybersecurity governance activities.

Compensation

$150,000–$200,000 per year as a W2, negotiable for the right candidate.

Benefits

• Medical insurance
• Dental insurance
• Vision insurance
• 401(k)