This chapter quantifies and analyzes the water and carbon footprints of household food waste in the UK. It traces where in the world water is used to produce the food and finds that the water footprint of avoidable food waste at household level in the UK is 6,200 million cubic meters per year, which is nearly 6% of all the water requirements in the UK. It is equivalent to 243 liters of water per person per day. A quarter of this footprint represents water used to grow and process food from the UK’s internal resources and the rest from outside the UK. Avoidable food waste is responsible for approximately 3% of the UK’s domestic greenhouse gas emissions, with further emissions from overseas components of the supply chain. In contrast to the water footprint, approximately two thirds of emissions associated with food waste occur within the UK, equivalent to emissions from over 7 million cars per year. It is also found that for some food and drink items, indirect emissions associated with Land Use Change caused by levels of demand for those items are greater than direct emissions. It is concluded that reducing food waste will not, by itself, solve all the problems of climate change and poor water management, but it can make a positive contribution.