Basic principles and details on the assessment of wastewater characterization are reported for metropolitan areas with significant industrial activities, with great capacity for future development. The conceptual approach related to the evaluation of pollution loads in terms of major parameters is defined both for domestic and industrial sources. Methods for extrapolating generated data for the future are discussed. A procedure is developed for the evaluation of the expected industrial pollution profiles on the basis of inadequate data. The proposed methodology is illustrated for Corlu as a case study, a region with rapid industrialization in Turkey. (C) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved.