Resumen
During 2007, East Africa has been the venue for an attempt to field-test the principles of spatial data infrastructures (SDIs). The effort has involved a self-motivated group of United Nations (UN) offices and programmes, and their partners amongst the non-governmental organizations, inter-governmental organizations, regional research institutions, and academia and beyond. The motivation for the exercise arises from the on-going definition of a United Nations Spatial Data Infrastructure (UNSDI) coupled with the recognition that there is little practical basis upon which to base such design, especially in the case of the governance structures necessary to sustain a co-dependent community of institutions that are building business applications over each others' data and services. A number of key points distinguish SDI-East Africa (SDI-EA) from equivalent ones occurring in more economically developed countries or regions in that it lacks top-down mandate or authority; there is a wide variety of institutional and legal frameworks governing data and service provision; the breadth and disparity of technical capability and infrastructure amongst the participants; the serious and pressing needs driving applications in areas as diverse as humanitarian response and protection, food security, and social and environmental vulnerability and adaptation to global climate change. The lesson emerging is that the constraints limiting effective SDI implementation are less to do with communications and technical infrastructure, and far more related to institutional misapprehension, "mission lock" and mistrust. Effective strategies for outreach, policy development and capacity building are considered.