New products and techniques are coming on the market at an ever-increasing rate to cover a wide range of needs: auditory diagnostics, hearing aids, cochlear implants, additional equipment (such as FM systems) and apparatus for checking and adjusting these assistive hearing devices. Although the early-intervention specialist does not have to know every technical detail, she needs to keep on top of developments in the technology so that she is, say, able to reflect together with the parents on the input they have received in consultations with doctors, hearing-aid acousticians or at the cochlear implant centre. She must also be able to check that the devices are working properly and advise parents or other caregivers on daily checks and maintenance. (see also module 3)