Trusted Security Services for Maryland, D.C., and Pennsylvania
Family-owned and led by a seasoned law enforcement professional, Defender One delivers reliable, responsive security—available 24/7 and tailored to your needs.
We Care About Your Safety
Defender One Security delivers trusted, comprehensive security solutions across Maryland, Washington, D.C., and Pennsylvania. Founded in 2009 by Baltimore native Jon Krieger, the company remains proudly family-owned and operated.
With more than 30 years in law enforcement—including leadership roles in patrol, internal affairs, traffic, and community outreach—Jon launched Defender One to bridge the gap between private security and public safety. That same commitment to professionalism, accountability, and community still drives the company today.
As a family-run business, Defender One offers a level of personal service and responsiveness national firms often can’t match. Jon and his wife Jennifer oversee daily operations, working directly with clients to ensure every detail is handled with care and integrity.
Trusted Security Solutions Since 2009
Decades of experience, grounded in law enforcement leadership and a commitment to professionalism you can count on.
Highly Trained Security Professionals
Our team is made up of skilled, vetted experts trained to deliver preventative, site-specific protection.
24/7 Coverage and Peace of Mind
We provide around-the-clock security through contracted services—ensuring consistent presence, not reactive response.
Family-Owned, Personally Committed
We’re not a faceless franchise. Every client matters, and every detail is handled with care by our leadership team.
Don’t leave safety to chance. Work with a team that treats it like a priority—because it is.
Our Comprehensive Security Services
Reliable Security Presence for Your Property
Uniformed security professionals stationed at your facility to deter threats, safeguard property, and ensure a safe environment. Ideal for corporate offices, retail, schools, healthcare facilities, and more.
Executive and Personal Security You Can Trust
Whether you need discreet protection for an event or long-term security for high-profile individuals, our team delivers peace of mind with professionalism and discretion. Transportation services available.
Fast, Professional Fingerprinting for Individuals & Teams
We offer efficient fingerprinting for employment, licensing, compliance, and more. Available for individuals or coordinated group sessions for companies and organizations.
News & Resources
How Community Partnerships Improve School Safety Measures
School safety remains a critical concern for every community. Meeting this responsibility demands a collaborative approach involving schools and local stakeholders, such as law enforcement, businesses, and parents. Strong partnerships foster a secure environment for...
Best Practices for Safe School Drop-Off and Pick-Up in Maryland
Safe school drop-off and pick-up routines are essential to fostering secure environments for students and families. In Maryland, adhering to best practices during these high-traffic periods helps mitigate risks, reduces stress, and ensures a smooth transition between...
Comprehensive Security for Religious Institutions
Religious institutions face unique security needs that go beyond traditional approaches. These sacred spaces, open and welcoming to all, require protective measures to ensure the safety and peace of mind for their communities. Comprehensive security for religious...
Emergency Drills Prepare Elementary Schools for the Unexpected
School safety goes beyond academics; it’s about preparing students to handle anything that comes their way. Emergency drills equip elementary schools with preparedness strategies, helping students and staff respond confidently to the unexpected. By familiarizing young...
Creating a Safe School Culture Starts With Our Community
Creating a safe school culture starts with our community fostering trust, open communication, and active involvement for lasting security. When communities support school safety together, they establish an environment where students thrive, feel secure, and grow into...
What to Do When a Security Threat Disrupts Worship Services
Houses of worship are places of peace, reflection, and community. Yet, in recent years, security threats have affected many such spaces, bringing the safety of congregants and staff into sharp focus. Knowing what to do when a security threat disrupts worship services...