Emil Hamilton served as the lab's director and chief scientist for the Metropolis branch. The lab was not limited to one area of study; everything from mutagenic studies to medicine was researched. Superman formed a research partnership with the organization where he allowed them access to his advanced technology; in return, they helped him cope with several problems he faced, such as his weakness to Kryptonite. He also came here to talk to Hamilton and seek his advice and assistance. The facility was also equipped to perform surgery and provide at least short-term medical care, as Superman brought Supergirl and Orion here for emergency treatment.
In the years leading up to the Cadmus Crisis, the organization seems to have been used as something of a front and tool for the Cadmus Project, as the theft of Kryptonite from the lab was orchestrated by Cadmus, with Emil Hamilton's knowledge. Also, some of the technology used by the Cadmus Project may have been developed here, as Professor Hamilton also occupied a senior position on the Cadmus Project's staff. Superman's alternate suits were housed here, including the anti-Kryptonite suit and a space suit.
The Paris branch of S.T.A.R. Labs was subject to a break-in by Kaznian operatives employed by Vandal Savage; despite the efforts of Batman, they successfully stole a targeting device later used in Savage's Mass Driver.
Parasite was housed at the Metropolis-based S.T.A.R until a special cell could be built for him at Stryker's Prison.