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
Partnering with Communities for Better Security Awareness
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How Hospital Security Protocols Help Save Lives
Hospital security protocols are essential to healthcare safety, protecting patients, staff, and visitors alike. These measures handle a range of risks, extending beyond access control to create a secure, responsive environment where lifesaving care can happen without...
Designing Safety Training That Sticks
Effective safety training is essential for every workplace. It helps employees gain and retain the skills they need to handle real-world scenarios safely and confidently. Designing safety training that sticks requires memorable, practical programs that help employees...
Debunking Private Security Myths
Private security often faces misconceptions that lead businesses to underestimate its value. Many people still think that private security merely means a physical presence or that a basic camera system covers all security needs. However, private security offers much...
Key Factors for Choosing a Reliable Security Firm
Choosing the right security company can mean the difference between peace of mind and vulnerability. Whether protecting a business, residential complex, or personal assets, selecting a reliable security firm is a critical decision that should never be rushed. With...
Uncovering Employee Misconduct Through Private Investigations
Private investigations provide businesses with essential tools for uncovering employee misconduct and protecting company assets effectively. When trust is broken within the workplace—whether through fraud, harassment, or mishandling of sensitive information—the...