LOCATION CHOICES OF REAL ESTATE AGENTS IN ISTANBUL After the 17th August 1999 earthquake, Istanbul has been adversely affected economically and socially. Significant differentiation in urban housing demand and supply has been observed. In this research, the distribution of real estate agents is examined with the help of GIS and the differentiation is scrutinized for the 1994-2006 period before the earthquake, and the period after the earthquake until 2006. The purpose of the research is to analyse; Housing production in the housing market in Istanbul, distribution of real estate agents, and differentiation of demographic, physical and land value characteristics of districts before and after the earthquake. It has been observed that close relationships exist between demographic and physical characteristics of districts and distribution of real estate agents.