||The symposium is part of a series of conferences devoted to remote sensing of urban areas. Starting in 1997 it continued in 2001 with an international audience from over 20 countries and approx. 130 participants. In addition to the oral and poster presentations an exhibition with company presentations was established. From 2001 onwards the symposium will be held on an annual basis. In 2002 it was hosted from Istanbul Technical University in Turkey. Due to a rising awareness of urban areas, agglomerations and mega cities an increasing number of participants was welcomed in Istanbul during the third symposium. Due to the overwhelming success of the first three symposia and due to the support from ISPRS, that in 2000 initiated a new working group "Human settlement and impact analysis" (ISPRS-WG VII/4) during the ISPRS-Congress in Amsterdam, it is a pleasure to announce the fourth symposium devoted to remote sensing of urban areas. The rapid advances in image acquisition and image analysis techniques call for the continuation of the discussions from the symposia held earlier. Urban growth and its associated problems are a very challenging task and suitable remote sensing and GIS applications could possibly assist in a wide range of applications for the wealth of urban areas.