D.S.I. is a company that was founded in June 1981. Since then, it has devoted its services exclusively to the creation of software programmes and the provision of services in the field of in Aluminium and P.V.C. fittings for exteriors. Out of a total of approximately 7,000 installations, about 500 are in Belgium, 3000 in France, around 100 in Spain, with those remaining in countries outside the EEC such as Canada, Egypt, Tunisia, Poland and the Czech Republic.