Abstract: Methods, systems, and apparatus, including computer-readable media, for authentication protocol management. In some implementations, a computing device receives data indicating a current context of a client device associated with a particular user. The computing device accesses first authentication data that demonstrates that the particular user has been authenticated using a first authentication protocol. The computing device determines that the particular user is likely to request access to a secured resource based on the current context of the client device and data indicating one or more previous resource accesses by the particular user. The computing device determines that access to the secured resource involves authentication using a second authentication protocol that is different from the first authentication protocol.