This thesis is a report of a study of some aspects of the architecture and urban planning of the M'zab Valley communities of southern Algeria, North Africa. The interrelation of physical planning and religious/social structures of the communities of the M'zab Valley are explored. This study was concerned with the following questions: (1) What are the various environmental factors that influence the design values of the M'zabites? (2) To what extent is the distinctive style of architecture in the M'zab due to religion: the Ibadi heritage or Islam in general? (3) How has the M'zab social structure responded to outside influences in recent years? (4) What is the present trend of the M'zab urban communities in architecture and planning?