In roof systems, high strength steel profiled sheeting fastened to high strength steel cold-formed purlins of lipped C or Z-section are commonly used worldwide. Their design is performed via AS/NZS 4600:2005 in Australia and the North American Specification for the design of cold-formed steel structural members in the USA. in both Standards, the method presented is limited to pure compression and pure bending without considering pure shear and combined bending and shear as occurs in a continuous purlin system. Three different tests were performed at the University of Sydney in order to extend the Direct Strength Method to purlin systems. April 2009, Univeristy of Sydney Research Report R894.