Madagascar was situated in the interior of Gondwana near the eastern edge of the east African orogen during late Precambrian to Cambrian time. As the east African orogen is thought to mark the join between east and west Gondwana, study of rocks of this age in present day. Madagascar may reveal important features essential for understanding the assembly of the supercontinent. The primary objectives of this study are to determine the nature of the terranes, timing of terrane accretion and terminal suturing in the eastern margin by extensive use of isotopic and geochronologic techniques. Results are expected to yield a more accurate picture of the temporal evolution of the east African rift, and an improved understanding of Madagascar's setting within the Gondwana supercontinent.