The text highlights the initiatives carried out by the city of San Francisco, to promote outdoor public urban spaces. Objectives, strategies and operating participatory methodologies are illustrated. The following programs are presented: “The Open Space Framework” for the realization of the “High Performing Open Spaces” network, the ROSE (Recreation and Open Space Element) which describes the urban policies for the requalification of open spaces, “The Better Streets Plan” that indicates the criteria used for the implementation of appropriate elements in the urban landscape, the “Green connections” Program for implementation of the ecological connections and “Pavement to Parks” which is a project conceived to help people reconfigure allotments of urban public spaces as places where one can relax and enjoy, achieved with low cost improvements, fast to realize and implement. Besides describing environmental, technological and processes aspects and the concept of parklets is illustrated. This has been proposed in the last project, emulated in many cities throughout the world with satisfying results that activated relations within the neighborhood, reconsidered the potential of urban streets, encourage walking and non-motorized transportation and support business activities. In light of the most updated international scientific literature, the text analyzes the Design Toolkits highlighting common aspects and specific characteristics. The possible technical alternative solutions are examined with requisites of the project, constructive technology and indications on the materials to be used. Finally, the Mint Plaza study case was presented describing the strategies of the local administration for storm water management. This is an example of intervention of urban requalification using private funds on public soil. Here special devices were adopted in order to delay, clean and maintain on the site the outflow from weather events. Highlighted in the conclusions are the need to create guide lines for the requalification of public outdoor spaces depending on the degree of persistence of the interventions, relating duration, strategy and technology, researching innovative and appropriate devices for reinventing the sites.