Electronic brachytherapy (eBT) is a type of brachytherapy treatment involving miniature X-ray tubes and has been implemented worldwide by several different manufacturers, selling for both interstitial and skin therapies. The radiation sources are comprised of small X-ray tubes operated with accelerating potentials less than 70 kV. Some sources are manufactured specifically for skin treatments, some are specifically for interstitial treatments, and some are capable of both types of treatment. A number of different detectors have been used to assess the dose distribution around these sources with different technologies and a variety of different approaches. The manufacturers’ recommended formalisms for calibration and dosimetry have been the most widely used, to date, in the absence of more formal societal recommendations. In this chapter, a variety of different detectors, including free-air chambers, commercial ionization chambers, diamond detectors, radiochromic film, TLDs, OSLDs, and others, are described along with their advantages and disadvantages.