South Dakota Investigative Services

GPS Tracking


Process Services

Infidelity Investigations

Background Checks

Information Checks

Locate Missing Persons

Locate Witnesses

Serving the following areas:

Sioux Falls, Yankton, Watertown, Madison, Aberdeen, Rapid City, Pierre, and Minnehaha County

Affiliates in:
Nebraska and Iowa

Looking for a Sioux Falls Private Investigator?

Licensed - Bonded - Insured

We can help you today!

Available 24 hours a day 7 days a week
Professional Discreet Confidential

Private investigators are being called upon more than ever with the information driven environment we live in today. PI’s are often the most reliable and efficient source of information.

Don’t spend another minute pondering your dilemma.
Call Allegiance for a free consultation.

Our Sioux Falls Private Investigators routinely assist businesses, attorneys, insurance companies and individuals with their investigative needs. Whether it’s renting a GPS tracker to determine where a person of interest is going, covert surveillance, finding someone, or digging for facts that you need call Allegiance Investigators.

Allegiance is a versatile investigative agency providing an extensive variety of services specializing in SURVEILLANCE. It’s been said many times before "in God we trust, everybody else we watch."

When your looking for the services of a private investigator in Sioux Falls or anywhere in the state of South Dakota call Allegiance Investigators first. We serve the entire state and also have affilitates in Nebraska and Iowa to help you.

Our Mission is to provide quality and timely service in a professional manner, while maintaining the highest ethical standards.

Contact Us Today

Allegiance Investigators
PO Box 87930
Sioux Falls, SD 57109