Using a interviews corpus of geographers from the theoretical and quantitative movement, this paper analyses how a team, the P.A.R.I.S. one, was progressively built as a proper laboratory. In an historical and spatial approach, its shows how the life of this laboratory is organized. This team was a major one in the general movement of the theoretical and quantitative geography in France from the beginning of the 1960's. It specifically renewed the urban studies, thanks to the quantitative and theoretical approaches. This team is compared to another one, the Dupont's group, who was also a major team in that movement, but differently organized. The focalization on one team, occasionnally compared to others, shows specific ways ot built a laboratory life. This paper pays a particular attention to the sociological, epistemological and spatial ways of its organization. On one hand, P.A.R.I.S. is a laboratory based in Paris but which includs a large number of women and young people. On the other hand, the Dupont's group is based in the South-East of France, it is more informal and mostly composed of men. In a period starting in the 1960's until today, this paper shows three moments of the construction of a laboratory in urban studies. Each moment participates to the institution of P.A.R.I.S. as a proper research's group.