Effective response to misuse or abusive activity in IT systems requires the capability to detect and understand improper activity. Intrusion Detection Systems observe IT activity, record these observations in audit data, and analyze the collected audit data to detect misuse. Privacy-Respecting Intrusion Detection introduces the concept of technical purpose binding, which restricts the linkability of pseudonyms in audit data to the amount necessary for misuse detection. Also, it limits the recovery of personal data to pseudonyms involved in a detected misuse scenario. The book includes case studies demonstrating this theory, and solutions that are constructively validated by providing algorithms.