The present invention relates to structural couplings for forming of a variety of structures such as floor and wall panels for buildings and internal structures such as hand rails. The structural coupling comprises a structural component or components (1) provided with coupling leg formations (2) and locking flanges (F) and a channel section (8) which interconnect one with the other by means of a snap fit engagement (12) of the leg formations (2) of the structural component (1) with the channel section (8). This has considerable advantages over the prior art where nuts and bolts were needed to fasten the components together. The use of a common channel section which can be engaged by snap fit action provides an elegant and non-limited method of joining structural components together rather than in a direct fashion as with prior systems.