This chapter shines the light on the foundations of geoprospective. The concept was born in the mid-2000s from the convergence of geographical researches which had in common to anticipate change in the long term and to evaluate its spatial impacts using simulations, with the aim of producing scientific knowledge that would at the same time be useful for action. The main characteristic of geoprospective is to be a spatial approach. Nevertheless, it has been given momentum and hybridized by several movements, foremost among these being prospective. Whether through their questionings or their methodological postures, the various forms of prospective have opened a new field of research devoted to assessing the future changes in ecosystems and anthroposystems, from which geoprospective derives. However, geoprospective has freed itself by focusing on the spatial change to come. This construction process conducted at the interface of spatial modeling, land change science, and spatialized participatory approaches is expounded in this chapter. The process helps to understand both the multiform character of geoprospective and the way it nowadays distinguishes itself from related approaches.