Spontaneous settlements are common phenomena in many third world countries. Although the different geographical locations, along with morphological factors, play an important role in shaping up different physical settings, dynamic social factors have similar consequences in such settlements. Ankara's gecekondu and Dhaka's bustees are in continuous change and adaptation into the structure of the cities in which they exist. Both remain as popular housing in the respective capitals of Turkey and Bangladesh. The aim of this paper is to find similarities and dissimilarities among gecekondu and bustees, giving an emphasis to five fundamental issues. Those are location of the settlement within the city, appropriation of land and ownership patterns, economic possibilities of the inhabitants, cultural and local dynamics of formation and uses of space, and last, the transformation of the settlements. Despite all physical and social dissimilarities, ownership patterns are perhaps the key factor in the development of such settlements both in Ankara and in Dhaka. The main commonality is that those settlements provide not only shelter but also possibilities to satisfy other needs for their inhabitants. © 2001 Elsevier Science Ltd. All rights reserved.