Portland Private Investigators, is an Oregon State Licensed Professional Private Investigation agency.
Duane Larson, owner of Cornerstone Investigative Services, Inc, is a dedicated investigator with over 30 years combined private investigation and law enforcement experience.
Cornerstone Investigative Services, Inc is a Private Detective Agency with a track record of delivering first-class professional investigative results throughout Oregon and Nationwide.
Our office is located in Downtown Portland in the World Trade Center.
Our Investigative Team is comprised of Licensed Private Investigators with extensive investigative experience including surveillance and covert undercover investigations. They are not identified here by the nature of their assignments. This protects their status and offers a greater level of security and confidentiality for our clients.
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