A builder, a design director, and trades who’ve been at it together for years.
Mark Stephen Development is a Winchester firm built around one belief: take on fewer projects, and build each one like it’s your own.
Built on twenty years of hands-on experience.
Mark Donnellan is the Principal Owner of Mark Stephen Development, a Winchester-based firm producing luxury custom homes and residential developments. With over 20 years in the industry and more than 50 completed projects across Winchester, Arlington, Medford, Somerville, and Cambridge, Mark brings deep local expertise to every build.
The firm takes on a limited number of projects each year to keep the work hands-on. Every project benefits from an on-staff design director, a trusted network of architects and trade professionals, and Mark’s own commitment to being present on the job site.
Mark is also a licensed real estate agent affiliated with Advisors Living, giving clients a rare combination of building expertise and market knowledge.
A house gets built. A home gets crafted. The difference is who’s standing on the site every week.
Small on purpose.
We work with a trusted bench of trade professionals who have worked to our standard for years. The same crews, project after project.
Four steps, no surprises.
Consultation
A conversation about your vision, timeline, and budget. Whether you’re buying one of our developments or exploring a custom build, we’ll walk you through what’s possible.
Design & Planning
Our team works with our architect partners on a design tailored to you, from layout to finishes. Every detail considered before ground breaks.
Build
Mark is on-site throughout, managing every trade and decision. You have direct communication with the team at every stage.
Delivery
We walk through every room together before handoff. Finished to a standard that’s ready to live in from day one.