The chapter discusses a new approach to transaction systems that aims to protect individual privacy and maintain security while preventing the creation of a dossier society. The current system, where organizations use identifying data to link records, is vulnerable to misuse by individuals and can lead to a chilling effect on personal activities. The new approach involves using digital pseudonyms for each organization, ensuring that transaction data remains anonymous and cannot be linked across organizations. This is achieved through the use of personal card computers that generate unique pseudonyms for each transaction, which are then verified using digital signatures. The system also includes mechanisms to prevent individuals from disavowing messages or payments, ensuring that all transactions are traceable only to the recipient. Additionally, the chapter outlines the use of blind signatures for untraceable payments and credential systems for managing relationships with organizations, all of which enhance security and privacy. The new approach is designed to be practical and secure, offering a solution to the growing problems of data misuse and abuse.The chapter discusses a new approach to transaction systems that aims to protect individual privacy and maintain security while preventing the creation of a dossier society. The current system, where organizations use identifying data to link records, is vulnerable to misuse by individuals and can lead to a chilling effect on personal activities. The new approach involves using digital pseudonyms for each organization, ensuring that transaction data remains anonymous and cannot be linked across organizations. This is achieved through the use of personal card computers that generate unique pseudonyms for each transaction, which are then verified using digital signatures. The system also includes mechanisms to prevent individuals from disavowing messages or payments, ensuring that all transactions are traceable only to the recipient. Additionally, the chapter outlines the use of blind signatures for untraceable payments and credential systems for managing relationships with organizations, all of which enhance security and privacy. The new approach is designed to be practical and secure, offering a solution to the growing problems of data misuse and abuse.