The document discusses various techniques used in corporate espionage, including hacking computers and networks, social engineering, dumpster diving, whacking (wireless hacking), phone eavesdropping, network leakage, and cryptography. It provides examples of social engineering techniques used by spies, such as unwittingly answering questions or bragging to coworkers. The document also notes that aggregation of information in one location can increase risks of insider or outsider attacks enabling espionage.