Senior ISSO: Zero-Trust Cybersecurity for Government Systems

Bart & Associates, LLC; Washington (District of Columbia); On-site; USD 125,000 - 200,000; Full time

Job summary

Bart & Associates, LLC is seeking a Senior Information Systems Security Officer (ISSO) to lead cybersecurity and RMF/ATO activities across enterprise systems. The role requires coordinating with government stakeholders and engineering teams to implement Zero Trust security architectures and maintain regulatory compliance throughout the system lifecycle.

Responsibilities include risk management, development of SSPs/SAPs/POA&Ms, security assessments, and routine coordination with ISSMs, ISSEs, and

Qualifications

• Active TS/SCI with Polygraph is required.
• Security+ or equivalent DoD IAT II/III certification required.
• 18 years of experience in Cybersecurity, IA, Security Engineering, or related field.
• Experience as ISSO/ISSE or similar role.
• Proficiency with RMF and XACTA.
• Experience managing IATT and ATO processes.
• Proficiency with Splunk.
• Experience with NIST 800-53 controls.
• Strong communication and stakeholder engagement skills.
• Experience supporting large government cybersecurity programs.

Responsibilities

• Conduct technical security assessments and evaluate system security posture.
• Ensure compliance with security frameworks and regulatory requirements.
• Support certification, accreditation, IATT, and ATO activities.
• Collaborate with developers, sysadmins, DBAs, and testers to integrate security across the lifecycle.
• Support security assessment events and remediation efforts.
• Develop and maintain SSPs, POA&Ms, SAPs, and assessment artifacts.
• Utilize XACTA to manage RMF documentation and authorization activities.
• Implement and validate NIST 800-53 controls.
• Apply Zero Trust principles to cloud-native and enterprise environments.
• Manage risk assessments, findings, mitigation strategies, and compliance tracking.
• Coordinate with ISSMs, ISSEs, System Owners, SCAs, and AOs.
• Support security monitoring and compliance reporting using Splunk.

Skills

TS/SCI + Polygraph

Security+ or DoD IAT II/III

18+ years experience

ISSO/ISSE experience

XACTA RMF familiarity

IATT & ATO management

Splunk

NIST 800-53

Zero Trust

Stakeholder engagement

Security documentation

Education

Bachelors in Cybersecurity/Info Assurance/CS/IS

Masters degree substitution for 6 years experience

Tools

XACTA

Splunk

Job description

Bart & Associates, LLC is seeking a Senior Information Systems Security Officer (ISSO) to lead cybersecurity and RMF/ATO activities across enterprise systems. The role requires coordinating with government stakeholders and engineering teams to implement Zero Trust security architectures and maintain regulatory compliance throughout the system lifecycle.

Responsibilities include risk management, development of SSPs/SAPs/POA&Ms, security assessments, and routine coordination with ISSMs, ISSEs, and