In the following a survey is given of what is known at present about the geology and petrology of Surinam. It must be understood that this outline cannot but be incomplete; in the first place because quantitatively our knowledge of Surinam is highly inadequate, and secondly because the same may be said concerning the insight into the geological relations between the different formations. Vast regions of Surinam have never been explored while besides in extensive areas exposures are very scarce. Interest in Geology, Mining, Topography and the research in the province of General Natural Science have directly or indirectly contributed to our knowledge. In the past century our knowledge principally grew by purely geological exploration. In this period fall Martin's operations in our Colony (1884—1885). Martin has published fundamental facts about Surinam¹). Besides Martin has given an impetus to important research performed by specialists²). After 1900 Mining-work came to the fore in connection with the Gold-industry; the topographical survey of the southern part of the Colony then also indirectly increased our stock of knowledge; of late years investigations have been multifarious.