"The amount of personal data stored in digital form has grown tremendously. All aspects of our lives are concerned. Our data include family pictures, insurance documents, bills and receipts, health records, cryptographic keys, electronic identities, certificates, and passwords. We store and process them on several personal devices as well as in the cloud via services such as Flickr or Facebook. Managing these data is challenging: they have to be updated, backed up, synchronised across devices, and shared. In case of emergency, health records must be accessible to doctors or designated family members. Many of these data are sensitive, but adequately protecting them is virtually impossible for private users with current tools.Encrypting data makes managing them only harder. It destroys much of the functionality that users have come to expect such as synchronising and sharing; mismanagement of encryption keys might even render data illegible to the owner himself.Our goal is to develop fundamentally new cryptographic primitives, protocols, and policy languages that let human users deal with cryptographic keys and encrypted personal data. We will invent mechanisms that 1) enable humans to securely store and retrieve cryptographic keys based on a single human-memorisable password, on biometrics, on hardware tokens; 2) enable end users to manage their various cryptographic keys and encrypted data via these keys; and 3) enable users and cloud hosts to perform useful operations on encrypted data without needing to decrypt. Our mechanisms will run on resource-constrained devices, i.e., they will be efficient and yet secure in the sense that they provide security guarantees, especially in the presence of untrusted cloud hosts.Our basic cryptographic research aims at infusing growth of a research community around protection mechanisms for end-user keys and data and to initiate follow-up collaborative projects to deploy our theoretical results in the real world"