demand, availability of inputs,and educational levels,
these only partially explain the disappointing rate of
progress in improving the productivity and income level of
the smaller farms and those with relatively severe
resource limitations.
 Examining the history of research and extension (R&E)
systems in the low- and middle-income countries of the
world reveals four distinct phases. The first phase,
which began prior to World War II, was marked by the
construction of a limited number of research stations,
either by public authorities or by international
corporations interested in improved technology for
commercial export crop production. Also, technical
training programs were started, often outside colleges and
universities. The focus of this first phase was on
scientific research and the exploration of new crop
production opportunities.
 The second phase, dating from the postwar period, was
characterized by a focus on rapid industrial development
and by the rapid expansion of publicly supported community
development and extension education programs for farm
families and rural residents. The explicit assumption was
that a backlog of technology available for adoption
existed, so programs should focus on technology transfer
and the motivation of target groups to accept change.
 When this technology transfer strategy did not give
the desired or expected adoption rates, a third phase was
initiated in the late 1950's, with renewed emphasis on
technology development and research institution building.
Research programs emphasized genetic improvement,
agronomic practices, and livestock management in an effort
to identify "packages of practices" appropriate for small
farms for which technology was not available. In this
phase, the international research centers came into
existence with their very strong, well-financed programs
of genetic improvement for major food crop species. At
the same time, cadres of scientists and agricultural
specialists from developing countries were trained,
leading to significant strengthening of their agro-biology
research systems.
 This third phase of agricultural research and
extension system development is responsible for the marked
growth in food production which has taken place in the
past two decades. Total food production in developing