The safe and effective treatment of biodegradable resources is increasingly being seen as a prerequisite for environmental protection in the context of preserving water quality, reducing greenhouse gasemissions and preventing the dispersal of human pathogens. One potential mechanism to meet this need is the treatment of organic resources by anaerobic digestion (AD), especially on-farm AD. The aim of this thesis was to place an economic value on the non-market environmental benefits of AD, above just being a source of renewable energy, through a combination of scientific and economic research. In chapter 4, digestate from manure subject to AD, undigested manure and synthetic fertilizer was applied to pasture (grass ± clover) grown in pots. It was found that there is potentially less leaching from digestate compared to synthetic fertilizer, with no negative impacts on yield. Chapter 5 was based on the same pot trial, and reports that the application of digestate affects the soil decomposer community in a similar way to that of synthetic fertilizer. Chapter 6 is the accumulation of a three year field trial comparing crop yield between synthetic fertilizers and digestate. Again, it was found that digestate application may replace synthetic fertilizer and maintain crop yields. Chapter 7 is an economic valuation of all the non-market benefits of on-farm AD. The valuation highlights the economic benefits of implementing on-farm AD as a management tool for organicresidues. This thesis is multidisciplinary in nature, encompassing microbiology, soil and environmental science, agronomy, and economics. An understanding of all these disciplines is imperative to properly value the benefits of AD both at a private level to the farmer, and at a public level to the wider community. The research indicates that AD is currently economically undervalued under the current renewable energy incentive (Feed-In-Tariffs; FIT) scheme run by the UK government and it is proposed that the FIT should be increased by £0.03 -0.15 per kWh of electricity produced via AD. This would substantially increase the FIT rate to between £0.12 -0.30 per kWh. Increasing the FIT to reflect all the non-market benefits that on-farm AD delivers would incentivise uptake of the technology and would facilitate the long-term viability of the industry. It would also rightfully reflect the fact that AD offers an effective pollution abatement technology as well as a source of renewable energy.