U-Prove is a free and open-source technology and accompanying SDK for user-centric identity management. The underlying cryptographic protocols were designed by Dr. Stefan Brands and further developed by Credentica and, subsequently, Microsoft. The technology was developed to allow internet users to disclose only the minimum amount of personal data when making electronic transactions as a way to reduce the likelihood of privacy violations. Security expert Bruce Schneier praised the cryptography behind U-Prove.