BACKGROUND : There has been a significant change in the types of substances consumed within English prison settings in the last eight years. There have been particular concerns regarding the acceleration in the use and availability of New Psychoactive Substances (NPS), mainly synthetic cannabinoids. Although NPS were identified as a 'problem' in prisons in 2011, government responses emerged only in 2015. As yet, there is no overarching policy document or strategy for dealing with NPS. This paper analyses the various strands of the response to NPS in prisons published from January 2015 to December 2016. METHODS : Drawing on Bacchi's 'What's the problem represented to be' framework, the ways in which the NPS 'problem' in prisons has been represented is analysed through a number of related policy texts including press releases, new legislative and regulatory measures, government documents and training package. RESULTS : From the various measures introduced to deal with the 'problem', NPS use is produced primarily as a law, order and control 'problem' requiring regulation, penalties and control, rather than a 'demand problem' calling for prevention, education, treatment and harm reduction or a 'regime problem' demanding greater emphasis and resources for purposeful activities such as education, training and work opportunities. This problematisation of drug use in prisons has a history dating back to the 1995 prison drug strategy and has become entrenched and reproduced within policy development over time. CONCLUSIONS : The law, order, and control problematization blames the volatility of the substances and the individual prisoners who use them as key factors contributing to the current prison crisis, rather than as consequences of the wider practices, cultures, contexts, and conditions. Multiple representations of the problem of NPS in prisons are needed in order to address the regime and structural issues which lead those imprisoned to use substances.