WELCOME TO

Cornerstone

About Us

Cornerstone Defense LLC is a Small Business servicing the Intelligence, Defense, and Space communities of the U.S. Government. Cornerstone Defense specializes in cloud architecture, enterprise engineering, systems and network engineering, systems and network security, and application and software development. We use these foundational technology areas to deliver solutions for data analytics, cyber, and space/mission operations, customized to meet mission requirements. We are headquartered in Herndon, VA, with employees working across the U.S including DC, MD, CO, UT, NM, HI, and CA. At Cornerstone Defense, you’ll find a partner that values strong relationships, excellence, and teamwork. Our team is a network of professionals who are dedicated to providing agile, secure, and efficient solutions to support mission success. With Cornerstone Defense, you’re not just choosing a service provider, but a committed, steadfast team with a culture designed to excel.

Vision & Mission

Meet The Team

Reilly Leonard

Chief Operating Officer

Reilly Leonard

Chief Operating Officer

Patrick Palmer

Chief Executive Officer

Patrick Palmer

Chief Executive Officer

Brian Sammons

Chief Financial Officer

Brian Sammons

Chief Financial Officer

Darcelle Wilson

VP of Human Resources

Darcelle Wilson

VP of Human Resources

Brandon Altmann

Chief Growth Officer

Brandon Altmann

Chief Growth Officer

Michelle Allen

Director of Systems and Security, FSO

Michelle Allen

Director of Systems and Security, FSO

Virginia Blair

Director of Marketing & Operations

Virginia Blair

Director of Marketing & Operations

Kaitlin Krywy

Managing Director, Aerospace & Defense

Kaitlin Krywy

Managing Director, Aerospace & Defense

Matthew Monroe

Recruiting Manager

Matthew Monroe

Recruiting Manager

WHERE CAN WE HELP?

To find out more information on where we can help you, services we provide,

joining or partnering with our team, please select one of the links below!

WHAT WE DO

We bring together a unique blend of cutting-edge capabilities, specialized expertise, and a remarkable company culture that focuses on the recruitment and retention of highly-sought-after employees.

Learn More

WORK WITH US

Search through all of our open positions.

Learn More

GET IN TOUCH

Contact Us
  • Virginia
    13454 Sunrise Valley Drive, Suite 100
    Herndon, VA 20171
    Maryland
    2288 Blue Water Blvd, Suite 330
    Odenton, MD 21113
  • eFAX
    443.769.1559
  • Phone
    703.691.5100
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Today, we honor Juneteenth—commemorating the end of slavery in the United States and recognizing the importance of freedom, justice, and equity for all.
 
At Cornerstone Defense, we believe our strength lies in our people. We’re proud to foster a culture that values inclusion, dignity, and respect—today and every day.
 
Let’s continue learning from the past and shaping a stronger, more united future—together.
... See MoreSee Less

Today, we honor Juneteenth—commemorating the end of slavery in the United States and recognizing the importance of freedom, justice, and equity for all.
 
At Cornerstone Defense, we believe our strength lies in our people. We’re proud to foster a culture that values inclusion, dignity, and respect—today and every day.
 
Let’s continue learning from the past and shaping a stronger, more united future—together.

🚨 INTERN SPOTLIGHT ALERT 🚨

Meet Nico — one of our summer interns! Nico’s a rising senior at Virginia Tech, majoring in Business, and he’s already bringing the energy, curiosity, and snack suggestions (hello, hummus & crackers 🧆) we didn’t know we needed.

👀 Want to know:
✨ What skill he wishes he could master instantly?
📺 Which fictional character he’d swap lives with for a day?
💼 What he’s most excited to learn at Cornerstone?
➡️ Swipe through to see all of Nico’s answers!

Let’s give a big Hokie welcome to one of the coolest interns around!
... See MoreSee Less

🚨 INTERN SPOTLIGHT ALERT 🚨
 
Meet Nico — one of our summer interns! Nico’s a rising senior at Virginia Tech, majoring in Business, and he’s already bringing the energy, curiosity, and snack suggestions (hello, hummus & crackers 🧆) we didn’t know we needed.
 
👀 Want to know:
✨ What skill he wishes he could master instantly?
📺 Which fictional character he’d swap lives with for a day?
💼 What he’s most excited to learn at Cornerstone?
➡️ Swipe through to see all of Nico’s answers!
 
Let’s give a big Hokie welcome to one of the coolest interns around!Image attachmentImage attachment+2Image attachment

⚠️ This is your sign. (Literally.)
We’re hiring. You’re cleared. Coincidence?
📸 Screenshot this and send it to a friend who’s ready to bounce. You might just change their life!
 
If you, or someone you know, has a TS/SCI with poly and are feeling underwhelmed, overlooked, or just plain over it… this might be the moment the universe (or at least Cornerstone Defense) sends you a nudge!
 
We’re hiring cleared professionals who are ready to do meaningful work and be treated like real people—not just a labor category. At Cornerstone, culture isn’t an afterthought. It’s the reason people stay.
 
✅ We answer your emails.
✅ We invest in your growth.
✅ We show up for each other—and have a little fun while we’re at it.
 
Learn more about Cornerstone on our website today (link in comments!)
... See MoreSee Less

⚠️ This is your sign. (Literally.)
We’re hiring. You’re cleared. Coincidence?
📸 Screenshot this and send it to a friend who’s ready to bounce. You might just change their life!
 
If you, or someone you know, has a TS/SCI with poly and are feeling underwhelmed, overlooked, or just plain over it… this might be the moment the universe (or at least Cornerstone Defense) sends you a nudge!
 
We’re hiring cleared professionals who are ready to do meaningful work and be treated like real people—not just a labor category. At Cornerstone, culture isn’t an afterthought. It’s the reason people stay.
 
✅ We answer your emails.
✅ We invest in your growth.
✅ We show up for each other—and have a little fun while we’re at it.
 
Learn more about Cornerstone on our website today (link in comments!)
1 week ago

🌟 One connection. That’s all it takes to spark a new opportunity, shift your career trajectory, or plant the seed for a future collaboration. Yesterday, our Director of Marketing & Operations had a blast attending a networking event hosted by the Loudoun Chamber of Commerce—an organization committed to building a stronger business community through advocacy, education, and connection. If you have never been to a Loudoun Chamber event, you must check them out some time. So many wonderful people to mee, and so many great opportunities!

The event was held at the stunning Morven Park mansion in Leesburg, VA—once home to Virginia Governor Westmoreland Davis and a historic estate now known for its equestrian center, museum, and lush gardens. The cocktail hour on the mansion’s grounds added a beautiful and meaningful backdrop to a night filled with conversation, collaboration, and new possibilities. Shout out to our friends at ResQ BBQ, also, for supplying the delicious food!

Big thanks to Loudoun Chamber for bringing together professionals who believe in the power of community. We’re always inspired by the reminder that you never know where a single conversation might lead.

Do you have any fun networking anecodates or stories about a connection you made that paid off in a big way? Drop us a comment and let’s chat about it!

@loudounchamber
... See MoreSee Less

🌟 One connection. That’s all it takes to spark a new opportunity, shift your career trajectory, or plant the seed for a future collaboration. Yesterday, our Director of Marketing & Operations had a blast attending a networking event hosted by the Loudoun Chamber of Commerce—an organization committed to building a stronger business community through advocacy, education, and connection. If you have never been to a Loudoun Chamber event, you must check them out some time. So many wonderful people to mee, and so many great opportunities!
 
The event was held at the stunning Morven Park mansion in Leesburg, VA—once home to Virginia Governor Westmoreland Davis and a historic estate now known for its equestrian center, museum, and lush gardens. The cocktail hour on the mansion’s grounds added a beautiful and meaningful backdrop to a night filled with conversation, collaboration, and new possibilities. Shout out to our friends at ResQ BBQ, also, for supplying the delicious food!
 
Big thanks to Loudoun Chamber for bringing together professionals who believe in the power of community. We’re always inspired by the reminder that you never know where a single conversation might lead. 
 
Do you have any fun networking anecodates or stories about a connection you made that paid off in a big way? Drop us a comment and let’s chat about it! 

@loudounchamberImage attachmentImage attachment+4Image attachment

👀 Let’s play a game—Cornerstone style! We’re throwing it back with five favorite photos from past team events—but there’s a twist: our logo is hidden in each one. Can you find them all?

At Cornerstone Defense, we work hard, but we also believe in making time for fun. Whether it’s team outings, volunteer events, or just celebrating the everyday wins, these moments reflect who we are beyond the job titles and clearances.

🔍 Look closely at each photo and see if you can spot our logo—some are easy, others… not so much!
💬 Found them all? Drop a comment and let us know which one was the hardest to find!

👉 Curious about what our logo really stands for, and the culture behind it? Check out our Culture page to learn how we empower cleared professionals while keeping things real, connected, and people-first (link in comments!)
... See MoreSee Less

👀 Let’s play a game—Cornerstone style! We’re throwing it back with five favorite photos from past team events—but there’s a twist: our logo is hidden in each one. Can you find them all?

At Cornerstone Defense, we work hard, but we also believe in making time for fun. Whether it’s team outings, volunteer events, or just celebrating the everyday wins, these moments reflect who we are beyond the job titles and clearances.

🔍 Look closely at each photo and see if you can spot our logo—some are easy, others… not so much!
 💬 Found them all? Drop a comment and let us know which one was the hardest to find!

👉 Curious about what our logo really stands for, and the culture behind it? Check out our Culture page to learn how we empower cleared professionals while keeping things real, connected, and people-first (link in comments!)Image attachmentImage attachment+2Image attachment
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