Companies and governments are increasingly using "Future Studies" for the design of their strategic planning. Techniques and methodologies are in very accelerated development all over the world. So it is necessary to establish the right set of tools and best way to use it in order to have results that you could compare and reproduce if you have in mimd to generate inputs for either companies or countries policy definition. This article describes the methodological approach adopted by a Brazilian Institution - Centre for Strategic Management and Studies - CGEE, mainly devoted to future analyses, and uses the recent examples of the Biotechnology and Nanotechnology foresight exercises in Brazil to show the real use of their results in the process for definition of national strategies.