Investigating the suitability of tropical clays for engineering applications is very essential due to daily encounter by practitioners as a result of ongoing massive engineering infrastructural constructions and the need for alternative and local materials that will ultimately reduce the overall project construction costs. Tropical clays from different locations and depths have been studied for potential applicability in engineering constructions. This was achieved by investigating index and physical behaviour through index and classification tests, mineralogy and fabric analyses through X-ray diffraction and scanning electron microscope, engineering behaviour through mechanical tests and determination of suitability index. The engineering applications considered were: the usefulness as foundation fill materials, sub-base and sub-grade materials, fill materials in embankment, waste disposal liner, brick making and archaeology materials. The clay materials have low to medium plasticity, dominated by kaolinites and characterised by agglomeration of particles into clusters with varying inter-cluster and intra-cluster voids. The majority of tropical clay samples can be classified as very good and good materials. They are suitable for use and can be applied by the practitioners for different engineering purposes depending on what they are needed for.