Traditional technics for amyloid are not always dependable. Therefore, several reactions, which do not require differentiation, were developed in this laboratory. This review describes technics that proved suitable for diagnostic pathology, including polarization and fluorescence microscopy. Effects of fixation on the reactivity of amyloid are also considered. The chemical mechanism of the alkaline Congo red, Mesitol WLS-Congo red and Phorwhite BBU reaction, and of a modified thioflavine T stain are reviewed briefly. Problems encountered with other methods, which cannot be recommended for diagnostic pathology, are outlined.