Member Marketplace

Welcome to the Alliance Allies Member Marketplace! The Member Marketplace is an online directory of businesses and consultants that specialize in serving nonprofit organizations in Connecticut.

The Alliance does not exclusively endorse the organizations listed in our Member Marketplace.
In order to qualify for discounts, your organization must be a member of the Alliance. For more information about membership, click here.

You can find participating businesses by category using the drop-down menu or through the search field. Click the name of the organization for company information and discount details. New vendors and categories are added regularly.

Guilmartin, DiPiro & Sokolowski, LLC

Contact: Michael Sokolowski, CPA, Partner
Work 505 Main Street Middletown CT 06457 Work Phone: 860-347-5689 Work Fax: 860-346-1172 Website:


Guilmartin, DiPiro & Sokolowski, LLC (GDS) has been in business serving the not-for-profit community for 45 years. GDS was founded in 1972 by Welles R. Guilmartin, CPA, initially offering general accounting services. During the 1980’s GDS began to focus and specialize in serving not-for-profit organizations that were funded by governmental organizations as well as private grants, fundraising, and service and membership fees. Since that time, GDS has continued to serve not-for-profit organizations that have a variety of missions and funding sources.

GDS currently provides services, including audit, tax and consulting to over 100 not-for-profit organizations, over 50 of which are subject to a State Single Audit and/or a Federal Single Audit. We perform services to not-for-profit organizations whose revenues exceed $50 million dollars to those well below the five hundred thousand dollar mark where an audit is not required.

Our not-for-profit clients engage in a variety of programs and revenue-generating activities to further their missions, including association and membership benefits, fundraising and capital campaigns, endowment management, volunteer and other in-kind services, and lobbying. GDS has grown to become one of the most highly respected accounting firms serving the not-for-profit community in Connecticut.

Our firm and our staff are educated in the unique characteristics and environments of not-for-profit organizations, including financial reporting and audit requirements, as well as Form 990 requirements. Our experiences with our not-for-profit clients offer us a unique perspective on the regulatory, financial and program environments in which our not-for-profit clients operate.