Superconducting composites are widely used in many industrial applications especially in electrical power transmission because of their amazing properties. The achievement of optimal performances (high critical current density and appropriated mechanical properties) requires a deep knowledge of the processing parameters of silver sheathed Bi-2333 composite tapes and copper sheathed MgB2 composite wires and tapes. In the PIT method each deformation step should be understood and controlled to insure the results of the whole process. Different mechanical deformation routes are possible in the PIT method such as swaging, extrusion, drawing and rolling in various shapes. A proper understanding of the processing parameters of these mechanical deformation processes and of the initial billet conditions will pave the way for an optimised fabrication process. The relationships between processing parameters, the conductor geometry and the physical properties are being utilised in the optimisation and control of the fabrication processes.