Thalezra was an independent world in the Alpha or Beta Quadrant, which had no treaties with any outside government, as well as an open immigration policy, making it a popular location for fugitives from justice on other worlds. The world was also noted for its architecture.
The USS Aventine visited Thalezra during one of its earliest missions, tracking down a wanted individual. Lieutenant Lonnoc Kedair was able to tap into the Thal database in order to find their target. In early 2381, Ensign Altoss was able to use the same method to locate a Ferengi named Sekki, who had purchased a mansion on Thalezra. (ST novel: A Singular Destiny)