Coherent optics and holography have become potential tools in offering tangible solutions to various problems in science, engineering, and medicine. Holography, with its three-dimensional nature and high resolution, finds applications in microscopy and macroscopy. Various holographic interferometric techniques are highly useful in diagnostic medicine. Coherent optical processors have remarkably high speeds and offer a parallel processing facility. Accordingly, these processors should be of great use in biomedical data processing like spectral analysis, correlation, image enhancement, etc. A survey of these techniques and their typical applications to problems in biomedical engineering has been given.