This chapter serves as an introduction to the book and provides brief information about urbanization in West Africa, and in Ghana in particular, the general role of urban agriculture and the common use of polluted irrigation water. It describes our focus on irrigated smallholder vegetable production and our understanding of the terms ‘urban‘, ‘peri-urban’ and ‘wastewater’. The chapter reflects on some of the key challenges of the farming system, its dynamic and resilience.

This paper assessed water management by households from three ethnic groups in two contrasting ecological settings (upland and lowland) in the Upper Ping River Basin in Northern Thailand. Important gender differences in the use and management of water were identified. Women are major users of water for agriculture in the uplands, but less so in the lowlands. In the lowlands irrigation is viewed as a masculine activity. In the uplands the role of women is more widely accepted, with women frequently being members of water user groups.

Using the farm as unit of analysis, diagnosis processes aimed at improving production systems are reviewed. Within a country, diagnosis should be conducted at different hierarchical levels: local (interaction between the production system and the input distribution sector, the marketing sector, possible forms of processing, and consumption characteristics); regional (appropriate selection of target site); and national (development trends and governmental policies at the macroeconomic and sectorial levels).

Low-impact development (LID) comprises a broad spectrum of stormwater management technologies for mitigating the impacts of urbanization on hydrological processes. Among these technologies, green roofs are one of the most adopted solutions, especially in densely populated metropolitan areas, where roofs take up a significant portion of the impervious surfaces and land areas are scarce.

Biological treatment, composting, in particular, is a relatively simple, durable and inexpensive alternative for stabilizing and reducing biodegradable waste. Co-composting of different waste sources allows to enhance the compost nutrient value. In particular, integration of ‘biosolids’ from the sanitation sector as potential input material for co-composting would provide a solution for the much needed treatment of fecal sludge from on-site sanitation systems, and make use of its high nutrient content.