D tarrayt swayes amdan s leɛqel-is, ad iheyyi ɣer sdat (planification rationelle). Deg useggas n 1950, yella-d umtawa ɣef usemres n unekmar s yiswan deg uḥric n ttrebya s tektiwin n Ralph TYLER. Deg tmurt n Fransa akked la Belgique, yella-d usemres n unekmaragi s wudem unsib deg usegas n 1970.