306 Enabling Policies and Institutions for Sustainable Agricultural and Food Systems
natural resources in a more sustainable manner. A great deal of information is
available on that issue (e.g. Howard, 1943; National Science Council, 1989; Rei-
jntjes et al, 1992; Pretty, 1995). Jiggins and De Zeeuw (1992) provide pioneering
information on Participatory Technology Development (PTD) for sustainable
farming, while Pretty’s (1995) authoritative book on regenerating agriculture pro-
vides a wealth of information on its feasibility and the conditions for transforma-
tion.
We do not limit ourselves to the field or farm level, but explicitly also take into
consideration larger-scale agroecosystems, such as water catchments, which need
to be managed in their own right in order to allow sustainable management at the
field and farm levels. Since this book assumes that the transformation to sustain-
able farming is social as much as agronomic and ecological (Vartdall, 1995), we
shall examine these agroecosystems by looking at innovation processes at levels of
social aggregation concomitant with the scale of the agroecosystem.
The contributors to the book bring along a wide range of experience assem-
bled during widely different life times, from widely different contexts, which allows
examination of the transition to sustainable agriculture from widely different per-
spectives, at different levels and along different dimensions (Box 16.2).
Box 16.2 Profile of the contributors
Campbell and Wagemans are senior policy makers in government, while Woodhill
plays the same role in an environmental voluntary organization. All three also under-
take consultancies in other parts of the world.Fisk, Hesterman and Thorburn work for the W.K. Kellogg Foundation (WKKF) in
various capacities. WKKF is a philanthropic foundation which supports learning in
and about agriculture and rural development.Boerma, Hamilton, Roux, Van de Fliert and Van Weperen play professional roles as
consultants, project leaders or implementors.Aarts, Gerber, Koutsouris, Papadopoulos, Proost, Van de Fliert (who has two jobs)
and Wagemakers work for universities as lecturers and researchers; Somers is a
researcher in a research institute.Blum, Castillo, Hoffmann, Pretty, Röling and Van Woerkum are university professors
who hold (or held, Castillo is emeritus professor) chairs in departments of extension
studies of one kind or another. Jiggins holds a chair in the field of human ecology.
Hesterman has worked as a professor in crop and soil science. All undertake con-
sultancies in various parts of the world.