Big Science organisations have a specific need for a range of diagnostics, detectors, and instruments for the scientific exploitation of the facility. The instruments are often designed by scientific and academic laboratories and universities, but the construction of these require the input from a multitude of specialized companies. The technical areas include optical components, imaging components, sensors, spectroscopic, microwave, electric & magnetic field diagnostics, particle detectors, opto-electronic detectors & components, and fast read-out electronics, etc.