Soils in engineering commonly refer to any kind of loose, unconsolidated natural material enveloping the surface that is relatively easy to separate by even gentle means (Terzaghi and Peck, 1967; Johnson and De Graff, 1988). Soils, three-phased materials consisting of solids, water and air, may be grouped into two broad categories of which one is residual soil, the other being transported soils of materials dislodged, eroded and moved via agents of transportation i.e. gravity, wind, water etc. and deposited at a different location. This chapter describes the residual soils found in the tropics, firstly, by looking at what they are and then the engineering approach in working with them, with the latter also requiring an understanding of their nature.