A hearing assistance device to be worn by a user, comprising: a microphone arrangement for capturing audio signals from ambient sound, an audio signal processing unit for processing the captured audio signals, and an ear-level output transducer for stimulating the user's hearing according to the processed audio signals, at least one wireless interface (18, 20, 42, 44) for signal reception from an external device (11, 40), a context detection unit for determining, by regularly analyzing signals received via the at least one wireless interface, present values of a set of context parameters, the context parameters being indicative of the present location of the hearing assistance device, with the context detection unit being configured to select, based on the determined present values of the set of context parameters, one location context out of a plurality of location contexts as the presently valid location context, and a security control unit for controlling security aspects of the hearing assistance device according to a security policy selected from a plurality of security policies, each security policy specifically setting security levels for access to services of the hearing assistance device; wherein each location context is associated with one of the security policies, and wherein the security control unit is adapted to select that security policy which is associated with the presently valid location context, and wherein the security levels of the security policies include at least one of: level of encryption of signals sent from the hearing assistance device to external devices, security level for access of external devices to the audio signals captured by microphone arrangement, security level for access of external devices to status data of the hearing assistance device, and security level for full access of external devices to the memory of the hearing assistance device. a microphone arrangement for capturing audio signals from ambient sound, an audio signal processing unit for processing the captured audio signals, and an ear-level output transducer for stimulating the user's hearing according to the processed audio signals, at least one wireless interface (18, 20, 42, 44) for signal reception from an external device (11, 40), a context detection unit for determining, by regularly analyzing signals received via the at least one wireless interface, present values of a set of context parameters, the context parameters being indicative of the present location of the hearing assistance device, with the context detection unit being configured to select, based on the determined present values of the set of context parameters, one location context out of a plurality of location contexts as the presently valid location context, and a security control unit for controlling security aspects of the hearing assistance device according to a security policy selected from a plurality of security policies, each security policy specifically setting security levels for access to services of the hearing assistance device; wherein each location context is associated with one of the security policies, and wherein the security control unit is adapted to select that security policy which is associated with the presently valid location context, and wherein the security levels of the security policies include at least one of: level of encryption of signals sent from the hearing assistance device to external devices, security level for access of external devices to the audio signals captured by microphone arrangement, security level for access of external devices to status data of the hearing assistance device, and security level for full access of external devices to the memory of the hearing assistance device.