The Círculo de Bellas Artes' exhibition Construction Toys, which gives rise to este catalogue, proposes an approach to the history of construction toys since their beginnings in the nineteenth century, which allows us to analyse the relationship between these toys and modern architecture. A fruitful relationship that goes in two directions: it is not solo that these construction block boxes have a high educational value, as architects of the stature of Le Corbusier, Gropius or Frank Lloyd Wright have recognized. In addition, the different toys that were coming onto the market were faithfully collecting the advances of las m avant-garde architecture, serving as formidable channels of dissemination.