A comprehensive, documented discussion of certain operating principles useful as guidelines for the analysis of industrial wastewaters is presented. Intended primarily for the chemist, engineer, or other professional person concerned with all aspects of industrial wastewater analysis, it is not to be considered as a substitute for standard manuals on analytical procedures, rather, as a guide for the effective use of the methods described in the manuals. Concern, therefore, is mainly with the design of measurement systems and theory of analysis rather than with stepwise procedures for analysis. Content includes discussion of: (1) the characterization of industrial wastewaters, (2) sampling, (3) analysis for major physical characteristics, (4) analysis for organic compounds, (5) analysis for metals, (6) analyses for nonmetal inorganic species, and (7) dissolved gases. Since the proper control of treatment processes and the evaluation of the pollution potential of industrial wastewaters are highly dependent upon precise and accurate measurement of impurities, industrial wastewater analysis is shown as a vital part of water pollution control. Three appendices provide information on miscellaneous organic matter, synthetic detergents, and nutrients; and a comprehensive bibliography lists related publications. This document is a reprint from "Treatise on Analytical Chemistry, Part III, Volume 2 (Industrial Toxicology" and "Environmental Pollution and Its Control)." (BL)