Real construction experience.
Real leadership.
Real outcomes.
Garrison Hill Group operates at the intersection of capital, operations, design, and construction. From feasibility through final delivery, we protect your budget, your schedule, and your outcome.
A comprehensive practice,
structured around you.
Six disciplines. One point of view. Every engagement is tailored to the specific pressures of your project and your capital.
No two projects are the same and neither are the people behind them. We tailor every engagement to where you are and what you need in the process.
Owner's Representation
We have worked in the field, run jobs, and managed millions of square feet for one of New York City's most prominent commercial real estate firms. We represent your interests from the first conversation to the final walkthrough.
Strategic Advisory
Before the design team is set. Before the budget is locked. Before the lease is signed. We get involved early so the decisions that matter most are made with the right guidance.
Portfolio Oversight
Multiple properties. Multiple moving parts. One trusted advisor across every asset in your portfolio, with the same level of care on each.
Development Consulting
Site evaluation, design team selection, feasibility. We help owners navigate the earliest and most critical stages of a development project.
Landlord / Tenant Coordination
Lease negotiations, tenant improvement dollars, scope division, and landlord obligations. We make sure you know what you have and what you are owed.
Construction Management
Hands-on oversight from preconstruction through closeout. Budget control, schedule management, and vendor accountability on every job.
You found us. Now let us show you why.
Every seat at the table.
Held.
Most advisors know one side of the process. We have worked all of them. As a tradesperson, superintendent, project manager on the general contractor side, and as Director of Design and Construction and Principal of the in-house general contracting operation at one of New York City's most prominent commercial real estate firms.
That is what makes our counsel different. It is not theoretical. It is lived, and it shows in the questions we ask before you sign a lease, lock a budget, or select a design team.
A career that began with tools in hand. We speak the language of the people actually building your project.
Superintendent, PM, and Principal roles delivering complex construction projects. Bridging the gap between design teams and construction teams, where budgets and schedules are truly tested.
Nearly a decade overseeing the most demanding commercial real estate projects in New York City. Complete oversight of the full construction cycle, from inception to completion.
Fluent in construction economics, value engineering, and what it takes to determine if a project is viable.
We bridge the gap between the design team and the construction team, making sure what gets drawn can and does get built.
Architects, engineers, contractors, and consultants. Everyone is held accountable to their scope and to a standard of honesty and integrity.
A record measured in
square feet and outcomes.
A selection of representative work across lobbies, tenant amenity spaces, workplace fit-outs, and fitness facilities. Additional detail available on request.
Strategic leadership,
not just project management.
We align stakeholders early
Teamwork is the foundation of every successful project. We identify misalignment across owners, design teams, contractors, and landlords and resolve it before it costs you time and money.
We bridge design and delivery
What looks good on paper does not always translate to the field. We make sure the design, the budget, and the reality of construction are all aligned so nothing gets lost between the drawing and the job site.
We protect capital and timeline
Sometimes that means preventing overruns. Sometimes it means an honest conversation about whether the numbers actually work before you commit. Unrealistic budgets and schedules are some of the most expensive problems in construction. We surface them early.
We hold everyone accountable
Architects, engineers, contractors, and consultants. Everyone involved in a project has a job to do. When everyone is held to a clear standard of honesty and accountability, the process works better for everyone, especially the client. That is what we push for on every project.
you do better."
Most people in this industry know one part of the process. They know the field or they know the boardroom. They know the contractor side or the owner side. Rarely both. Rarely all of it.
Dermot O'Sullivan has spent two decades doing all of it. He started his career in the trades, working as a carpenter and learning construction from the ground up. He moved into superintendent and project management roles on the general contractor side, where he learned what it actually takes to deliver a project in the field. From there he made the move to the owner's side, spending nearly a decade overseeing some of the most complex commercial real estate projects in the Tri-State Area.
Throughout every role, one thing remained constant. Dermot found himself in leadership positions not because he sought the title but because of how he works. With honesty. With integrity. Owning every decision, every outcome, and every lesson along the way. Garrison Hill Group was built on those same values.
Owners deserve an advisor who has actually done the work, who will tell them the truth, and who genuinely cares about the outcome. That is what GHG is. That is what Dermot brings to every engagement.
Your project deserves
real leadership.
If you have a project, an idea, or just a question you do not know who to ask, reach out. The first conversation is always on us.
dosullivan@garrisonhillgroup.com→