Atomic X-ray spectrometry has the same needs as other forms of optical spectroscopy: a source of X-rays, a means for isolating a desired range of wavelengths of X-rays, a means for detecting the X-ray...Atomic X-ray spectrometry has the same needs as other forms of optical spectroscopy: a source of X-rays, a means for isolating a desired range of wavelengths of X-rays, a means for detecting the X-rays, and a means for converting the signal at the transducer into a meaningful number. In this section we explore each of these needs.