From publisher blurb: The material contained in Setting Update #1 is not only suitable for the Twilight Sector Setting but for any Traveller game invloving high-density cities, clone technology, secret organizations and other common sci-fi themes. This product will provide a further glimpse into the Twilight Sector and serve as a players guide for the Beyond the Open Door adventure campaign. Stripped of all the adventure specific information from Beyond the Open Door this product provides all the down and dirty background information that players will want to know.