New Sydney was the seventh planet in the Sappora planetary system, known for its richness in pergium. New Sydney was an independent planet, heavily influenced by the Orion Syndicate. It was also the birthplace of Ezri Dax, neé Tigan, and remained the home to Yanas, Norvo, and Janel Tigan.
The planet had its own police force, the New Sydney police bureau. Lieutenant Fuchida was one such police officer who worked for it. The planet also suffered problems with pollution – Miles O'Brien, while investigating a murder on the planet, remarked that a body found in a river had been partially decomposed by organic solvents in the river.
The Tigan family owned a large business on Sappora in the 24th century. By the 2370s, the Orion Syndicate had begun to establish itself on the planet, represented by Thadial Bokar. (DS9: "Prodigal Daughter") However, Syndicate member Liam Bilby considered New Sydney a safer home for his wife and children than Farius Prime. (DS9: "Honor Among Thieves")
Due to its vast mining usage, New Sydney was inhabited and visited by a large variety of species, including Farians, Humans, Trill, Ferengi and Nausicaans. It was a non-Federation world, where Starfleet had no jurisdiction. (DS9: "Prodigal Daughter")