Private Investigators Serving Long Island
Discreet investigative support for individuals, attorneys, insurers, employers and businesses throughout Nassau and Suffolk Counties.
Local Knowledge. Professional Investigative Support.
Long Island assignments can require familiarity with local communities, courts, businesses and travel patterns. GSI brings decades of investigative experience to matters ranging from background research and surveillance to insurance investigations, litigation support and locates.
Nassau County
Investigative services throughout Nassau County for legal, insurance, business and private matters.
Explore Nassau CountySuffolk County
Investigative services throughout Suffolk County, including communities across the North Shore, South Shore and East End.
Explore Suffolk CountyInvestigation Services on Long Island
Surveillance
Discreet field surveillance and documentation for appropriate investigative matters.
Learn about Surveillance →Insurance Investigations
Field and investigative support for claims professionals, carriers and related organizations.
Insurance Investigations →Litigation Support
Investigative research, trial preparation support, locates and case development.
Litigation Support →Background Checks
Background research for individuals and organizations, with nationwide capabilities where available.
Background Checks →Discuss a Long Island Assignment
Contact GSI for a confidential review of your investigative needs.
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