On-farm conservation involves the maintenance of traditional varieties by farmers in agroecosystems. The important role of small farmers living and cultivating in complex, diverse and risk-prone marginal and heterogeneous environments in maintaining crop diversity on-farm is described. The on-farm conservation of plant genetic resources is complex because there are many factors that will influence a farmer’s decision on the management of their crops and fields, which in turn affect the quantity and quality of the inherent genetic diversity. The multiple private and public values and benefits of on-farm conservation are highlighted, as well as the options and interventions that can help strengthen the role of small farmers and farming communities in on-farm conservation. A major focus for the conservationist or development practitioner will be to encourage the farmer to continue cultivation of traditional varieties and this may be achieved by niche marketing, seed shows, participatory traditional variety improvement or even financial incentives. Key steps that need to be considered when implementing an on-farm conservation project are outlined and a brief review of the impact of on-farm conservation projects and the implications for scaling up actions is provided.

There is a strong social and ethicalpolicy context to plant genetic resources conservation and use. This is achieved by providing the historical background, introducing the major conventions, treaties and agreements, as well as the key stakeholders from the formal and informal sectors that are concerned with plant conservation, use and the equitable sharing of benefits. An attempt is made to assess the impact of the CBD and other conventions and to provide a balanced summary of the continuing debate on key issues such as ex situ versus in situ conservation, hotspots of botanical diversity and ex situ conservation and plant breeders’ rights, farmers’ rights, access, release of transgenic plants and sustainability both in conservation and use.