In the year 1994, the North American president, Clinton, published a presidential order to develop the National Spatial Data Infrastructure of the U.S.A (NSDI) (1). This initiative was developed in response to the need to facilitate the reuse and sharing of existing data resources. The efforts should be concentrate to collect and provide access to geospatial data. The starting keys points can be resume as (2) :

• users are not aware of the existence of data

• users have no idea whether or not a certain data set meets their application requirements

• this has led to considerable duplication of efforts and waste of resources

The FGDC ( Federal Geographic Data Committee), an interagency committee, obtained the leardership role to coordinate the development of NSDI nationally. Since then, the SDI concept was transposed at global scale. We can note the SNIG in Portugal, Australia’s ASDI, Malaysia’s NaLIS, South Africa’s NSIF, Colombia, or recently the multi-national INSPIRE Initiative in Europe.

The acronym of SDI (Spatial Data Infrastructure) is often used to denote the relevant base collection of technologies, policies and institutional arrangements that facilitate the availability of and access to spatial data. The SDI provides a basis for spatial data discovery, evaluation, and application for users and providers within all levels of government, the commercial sector, the non-profit sector, academia and by citizens in general.

Bibliography

(1)  http://www.fgdc.gov/policyandplanning/executive_order/?searchterm=clinton

(2)  http://www.ncgia.ucsb.edu/education/curricula/giscc/units/u190/u190_f.html