Aims of the survey are to raise the level of security awareness and to determine the scope of computer crime in the United States. Based on responses from 521 security practitioners in U.S. corporations, government agencies, financial institutions, and universities, the 1999 survey confirms trends established over the last three annual surveys. Findings indicate that computer crime and other information security breaches pose a growing threat to U.S. economic competitiveness and the rule of law in cyberspace and that financial costs of computer crime are tangible and alarming. Specifically, computer system penetration by outsiders increased for the third in a row, and 30 percent of respondents reported intrusions. Unauthorized access by insiders also rose for the third straight year, and 55 percent of respondents reported such incidents. Financial losses due to computer security breaches amounted to over $100 million for the third straight year as well, and 163 respondents reported a total of $123,779,000 in losses. There was a dramatic increase in the number of respondents reporting serious incidents to law enforcement. Survey findings are detailed with respect to respondent characteristics, security technologies, types of computer security breaches, and web site and e-commerce attacks. 2 tables and 17 figures