Regional, National and International Consulting and Professional Investigations

Cornerstone Consulting Services, LLC is a consulting and investigative company which provides a wide array of professional consulting and investigative services to our clients. Cornerstone was formed by Mark J. Zaba and Brian P. Smyth who retired as Special Agents with the Federal Bureau of Investigation (FBI) following 55 years of combined experience with the FBI. Since our founding, we  have established ourselves as being a premier investigative and consulting firm providing services to Law Firms, Corporations, Private and Public Companies and Private Individuals.

Cornerstone is a licensed and bonded private detective business in the Commonwealth of Pennsylvania. Headquartered near Philadelphia, Pennsylvania, we combine our deep local knowledge with the expertise of world-class professionals to assist our clients in helping them to meet their needs. Cornerstone regularly performs a full range of traditional investigative services in the greater Philadelphia area.

Cornerstone provides global reach for our clients’ consulting and investigative needs by providing services through our strategic partnerships. Cornerstone is networked with other former Special Agents of the FBI, other former federal agents, and other vetted investigators and consultants. Through these associations, Cornerstone offers consulting and investigative services in all 50 states and most countries throughout the world.



Integrity, Expertise, and Professionalism

Cornerstone provides honest, confidential and ethical services to our clients while at the same time maintaining the highest standards for professionalism. Our primary goals are to preserve client assets and maximize their profits and efficiency. We approach our clients issues with discreet sensitivities.  Cornerstone is uniquely positioned to offer consulting and investigative services that focus on mitigating risk or reducing unnecessary investments by our clients. Our experience and professionalism is your assurance of a comprehensive and results-oriented cost effective investigation which is focused on client objectives.  Cornerstone ownership has realized consistent results from the integrity of our staff, the quality of our work and our global network of resources. As a result, we enjoy a solid reputation for outstanding consulting and investigative expertise. We have implemented quality control standards to ensure thoroughness and accuracy in our work product. Expert witness testimony is available for select services that Cornerstone provides.

Cornerstone has provided solutions to our clients by focusing on their objectives and resolving issues that have been of  concern to them.  While most of our clients are attorneys, business or professional corporations, on a selective basis, Cornerstone will accept cases directly from private individuals.  Our investigative and consulting practices are performed confidentially, timely and legally.  Most of our clients are attorneys, both public and non-public companies, religious institutions and other entities that must adhere to ethical standards.  Cornerstone will never guarantee the outcome of an investigation or assessment and our fees are not subject to the outcome of any case.  The facts of the investigation will compel the results.  Our professional  backgrounds are consistent with providing quality consulting services and investigations that are confidential.  Through our collective experiences and past associations, as well as our established network of trusted  national and international strategic partners, Cornerstone will coordinate investigations and consulting in the United States and internationally. 

Cornerstone’s Pennsylvania Corporate Headquarters
41 University Drive,  Suite 400
Newtown, Pa.  18940
(215) 493-0439

Cornerstone’s New Jersey Office
116 Village Boulevard, Suite 200
Princeton, New Jersey  08540

Cornerstone Consulting Services, LLC is a licensed, bonded and insured company.
•    Private Detective License  – Commonwealth of  Pennsylvania – PI #220
•    Private Detective License – State of New Jersey – PI #License Pending

Our Mission

To provide quality, professional investigative or consulting services and meet the needs of Corporate entities, the Business Community and Private Individuals in the most practical, efficient and effective way.