This paper reports a synthesis of policy-relevant evidence on household waste prevention, based on a UK portfolio of primary research and a broad international review. Waste prevention was defined as strict avoidance, reduction at source (e.g. home composting) and reuse (for the product’s original purpose) — recycling was excluded. A major focus was on consumers. Waste prevention is not one but many behaviours; the review revealed a general hierarchy in their popularity, from donating goods to charity at the top; through small reuse behaviours around the home; to activities involving changes in consumption habits at the bottom; one estimate is that 60% of the public does at least one of these activities, some of the time. Barriers to engaging householders include both modern consumer culture and a genuine confusion that waste prevention is equivalent to recycling. The public can be engaged through local or national campaigns, with a wide range of interventions and communications approaches available. On the products and services side, the primary opportunity within the scope of the review was identified as increasing reuse. The barriers included operational difficulties (funding, capacity, logistics) and consumer attitudes towards second-hand goods. The main opportunities are to ensure more strategic planning for reuse by local authorities and better co-ordination and joint working with the third sector. The review examined the impact or potential of various policy measures designed to influence household behaviour directly or the products and services provided to them. Overall, the international evidence suggests that waste prevention benefits will be derived from a ‘package’ of measures, including, for example, prevention targets, producer responsibility, householder charging, funding for pilot projects, collaboration between the public, private and third sectors, and public intervention campaigns. UK evidence suggests that the greatest tonnage diversions can be achieved on food waste, home composting and bulky waste. The principal evidence gaps relate to robust and comprehensive quantitative data. Better evidence is needed of what actually works, and what outcomes (weight, carbon and costs) can be expected from different measures. More sensitive and effective monitoring and evaluation is needed to provide the evidence required to develop the necessary basket of future policy measures at local and national level.