The natural resources inventory of Kalimantan Timur has proven the value of remote sensing techniques as an approach to a modern resources inventory. Under the given conditions of poorly accessible, heavily vegetated areas, the limitations of knowledge, and time and fund restrictions, there was practically no other choice. In the case of the Kalimantan Timur resources exploration, the combination of the three different techniques turned out to be very advantageous. Besides, it was one of the few instances in the world so far, where SLAR surveys have been carried out.