The manual presented here is based on the experience and draw out the collected lessons learnt with regard to the design and implementation of TIGA project in the South Asia and Sub-Saharan Africa. As such, this builds on and expands existing guidelines and documentation for agricultural technology assessment. It adds the perspective of technology assessment of including the cross section of segments of the rural poor characterized by varying degrees of overlapping human capabilities and agro-ecological potentials rather than the technology-driven approaches that tend to favor those with better adoption capabilities. The manual also gives the reader a well-documented experience of bottom-up approach for technology assessment.