Hacking and espionage activities are being perpetrated in increasing amounts today. The intentions behind such hostile acts may range from trivial ones like curiosity or the thrill of an intellectual challenge, to more sinister ones like gaining sensitive information for personal benefits or for causing severe economic losses to a business or ideological rival.

According to a recent survey of Fortune 1,000 companies and the 300 fastest-growing US companies that was conducted by the American Society for Industrial Security, the potential loss to corporate America from the theft of intellectual property may soon amount to more than $300 billion a year.

In this paper, we will study the differences between hackers, who are the more gentlemanly types, and crackers, who are the real troublemakers. We will also discuss the various ways in which such entities make inroads into a victim's home or a rival's organization, and with this information at hand, we will attempt to discuss strategies to thwart the common forms of corporate or personal espionage activities.