A field configurable device, such as an FPGA, supports secure field configuration without using non-volatile storage for cryptographic keys on the device and without requiring a continuous or ongoing power source to maintain a volatile storage on the device. The approach can be used to secure the configuration data such that it can in general be used on a single or a selected set of devices and/or encryption of the configuration data so that the encrypted configuration data can be exposed without compromising information encoded in the configuration data.