"The incapacity of the State in the developing world in general and in Agentina, particularly to face the growing housing deficit for the low and middle-low income groups has push the national and local governments to look for new solutions. The availability of a national fund for housing (FONAVI) get through taxes, constitutes an essential resource but not enough to solve the problem, adding furthermore housing emergencies created by natural disasters, typically flooding, in the context of a growing unemployment rate. Innovative solutions explored include institutional partnership to implement common projects: Public-private partnership applies to affordable projects with components of rentability, such as middle income groups; public-non governamental partnership applied to low income housing. The Municipal Commission of housing of the Autonomous Government of Buenos Aires, currently works through both modalities of partnership: Articulating investments with the private sector in projects orientated a middle income groups and financing non governamental groups, cooperatives and enterprises to build low income housing projects. In the first group it can be mentioned the programs ""Casa Propia"" and ""Terreno, Proyecto y ConstrucciÛn"" both based on the call to private investors to present proposals with their own land, providing the local governments financial resources for construction. In the second group it can be mentioned many programs orientated to marginal population living in shantytowns, in illegal settlements, etc, calling to non-governamental groups to present projects, also providing finance for construction upon the base of the property of land. It means that the key for the viability of projects in both cases of partnership is the availability of urban land. The city of Buenos Aires faces an important shortage of available land, together with an important increase of prices. The result is the reduction of social projects and the increase of investment projects orientated to medium and high-income groups, excluding the low-middle and low-income groups of the city. The southern area of the city has important possibilities to generate vacant land where to build social projects. The central problem is the lack of information respect to cost and localization for decision making. This research develop a methodology orientated to create an instrument for analysis and information useful for designing investments in the field of housing with special emphasis in middle and low income housing, through survey of available vacant land, market analysis and monitoring the incidence of the cost of land in housing projects. Some preliminary conclusions include the issues of land speculation as result of the legal framework of the public call to present projects; and the sustainability of the social market in the context of the rules of the current real estate management rules in the city of Buenos Aires."