Data service companies are vendors of databases. These companies provide access to a number of databases, sometimes within one subject area and sometimes in a variety of subject areas. For example, NPIRS offers access to six pesticide related databases, while Ovid offers access to a variety of databases in seven different subject areas. Most data service companies are commercial companies, but universities and trade associations may also sell access to their databases.

Data service companies often require a subscription to use their services, but the subscription usually entitles subscribers to customer support and reference documentation. Some also offer a periodic newsletter. Others may not require a subscription but rather will charge by access time or types of information searches required. Many data service companies offer their databases via online access and also via CD-ROM.

Some data service companies offer staff or valet searches of their databases for a fee. This may be cost effective, however, particularly if you don't know what databases to search for the information you need. Other services offered by some data service companies include forecasting, assessment, and legislative tracking.

Data Networks refer to sites or organizations that provide free access to more than one database. Generally these are online sites that provide access to a number of related databases. In many cases, users can access data networks at a Web site and use their browser to conduct keyword searches or browse selected databases. Some data networks may charge for access to certain portions of their data.

Keep in mind that the same database information may be available from several different data service/data network companies and/or individual databases. For example, the RTK NET provides free access to a variety of databases (CERCLIS, FINDS, ERNS, Docket, etc.) that may not always be free through other database providers.

Data service companies and data networks are referenced in the EnviroSource.com category Databases.