The histochemistry of carbohydrates demonstrated by means of physical development procedures has been reviewed in terms of the use and reliability of the procedures, physical developers, practice of the procedures, a fundamental series of light and electron microscopic methods and certain other promising aspects of this area of histochemistry. A line of fundamental light- and electron-microscopic histochemical methods for carbohydrates using physical development procedures such as periodic acid-thiocarbohydrazide-silver protein-physical development (PA-TCH-SP-PD), high- or low-iron diamine (HID or LID)-TCH-SP-PD and lectin-gold (LT-G)-PD and related methods has been found to be more efficient, compared with those without physical development procedures. Since a series of other promising histochemical methods for carbohydrates using physical development procedures have been derived or are now being introduced, these procedures could be regarded as an unusually potent vehicle for effectively advancing carbohydrate histochemistry in both light and electron microscopy.