The department of Puno surrounds lake Titicaca (3 800 m above sea-levet) and extends over a vast stretch of land (the altiplano) and the Andean ridges (the puna) spilling northward into the Amazonian basin (the selva). Through fied work information and the use of census returns (1940 and 1961), this paper attempts to assess the evolution and the interdependance of Puno's main populated centres on the one hand, and to develop a general scheme of regionalization based on geo-spatial structures and administrative lay-outs on the other. In addition, the nature of settlements is briefly outlined and a more detailed quantitative analysis (30 variables, 85 districts) shedding some light on the internal departmental patterning is attempted. In conclusion, it is suggested that the planning process should result in a successful compromise between two sets of characteristics : spatio-economical elements (planificación tecnocrática) and social-cultural elements (planificación de base).