Introduction : 1. Online Searches : Types of Searches and Methodology; 2. Survey of the Available Databases, Their Services and Access Conditions; 3. Description of the General Types of Equipement used for Online Access to Patent Databases; 4. Guidelines on the Interrogation Online by Using Telex, Personal Computers, Computer Terminals; 5. Staff Matters and Financial Aspects; 6. Sample Searches; Appendixes: Survey of Operators and Comands; Information on Individual Databases; Example of Online Interrogation by Using a Computer; Database Rates (in USD as of February 1, 1991); Example Prints of Online Searches; Annexes : Some Useful Explanations of Technical Terms; Summary of Experience Gained in the Use of Computerized Search Systems Presented According to Individual Databases; Addresses of Selected Database Producers and Online Service Suppliers; Example Telex Connections to Several Online Hosts; Bibliography;.