The approach to housing and residential planning has never been coherent, as for some governments housing is a 'welfare parameter', while for others it is a 'product for consumption'. Despite all the planning mechanisms, housing has always been a problem in some countries. This might be because of the fact that usually the symptoms, and not the causes, have been addressed.
There is little difference in the nature of the housing problem in both developed and developing countries, in spite of the fact that in the former, access to low- cost housing forms the problem, while for the latter the demand for low- cost housing with a better quality is the core issue.
The housing problem in Tehran should be viewed both as a national crisis as well as a metropolitan concern. It has many dimensions which are reflected in the increase in housing costs (both rent and purchase), migration of some households to marginal settlements, lack of appropriate housing for different income groups, deterioration of existing housing stock, real estate speculation on new housing, etc. The housing market is seriously affected by values, illusions, consumption patterns, and decisions of non- public sector. Insufficient inappropriate intervention of public sector with no clear definition of goals has led to inadequate constraints for controlling the housing market. It is thus dominated by private sector activity with a single objective of maximizing profit. Consequently the 'housing problem' in Tehran can be described by the lack of a common adequate approach and the lack of an appropriate mechanism for control of housing spatial structure.