The significant challenges raised by the habitual, low involvement behaviours that surround food management in the home make it hard for campaigns to achieve behaviour change. This chapter focuses on food waste in households and how marketing and psychology can help in its reduction. The Trans-theoretical Model (TTM) is introduced as a psychology model that can help establish where people are on the behaviour change spectrum and can be used to tailor campaigns and measure change. The model is fully described proposing that people move through five change stages – pre-contemplation; contemplation; planning; action and maintenance. Additional TTM measurable concepts are discussed including decisional balance (weighing up the costs and benefits of change); processes of change (using ten specific cognitive and behavioural processes); and self-efficacy (belief in one’s own ability to change). The chapter concludes with a case study on the delivery of a TTM guided food waste prevention campaign in Australia.