The ‘psy’ (the psyche, the mind, mental health, subjective wellbeing, cognition, subjectivity, mentality, and more) is fast becoming a specific frontier of international development. This marks the further individualisation and psychologisation of poverty. Furthermore, when situated within wider power dynamics, subjugation and global capital, the psychological domain is targeted for instrumental purposes by political and economic actors, having neo-colonial implications. This area of research takes up these concerns and critically examines the use of psychological expertise within development policy and practice.