Tolerance modelling, assembly variation modelling, statistical tolerance analysis and variation propagation control are the constituent part of the assembly design and these are very important for quality manufacture of mechanical products. Various methods have been developed for tolerance modelling, assembly variation modelling, statistical tolerance analysis and variation propagation control. This paper thus provides a review of the literature in the area of assembly modelling; mainly focusing on the literature related tolerance representation, modelling assembly variation propagation and assembly variation control.