Loess and loess-derived soils cover much of Canterbury, from the foothills of the Southern Alps to the Pacific Coast. These soils are of variable thickness, ranging from several metres up to 40m at the base of slopes on Banks Peninsula. In many areas primary, air-fall loess has been reworked by slope processes to form a loess colluvium. These soils are comprised predominantly of silt but can contain up to 45 % clay, giving rise to low plasticity clay behaviour. Loess and loess-derived soils are relatively dense, and can form vertical exposures. Dry densities are typically between 1.6 t/m3 and 1.8 t/m3, hence these soils do not display collapse behaviour common to other loess deposits around the World. Across Canterbury these soils display high dry strength but weaken rapidly with small increases in moisture content. Periodic wetting leads to a variety of slope failures related to internal erosion (tunnel gullying) and rapid loss of shear strength (debris flows and soil slides). In this paper, we present a methodology to investigate the effects of soil microstructure and soil suction on the shear strength and stability of loess soils in Akaroa Harbour.