With prescribing expenditure rising and evidence of prescribing costs variation, general practitioners (GPs) in the UK are under increasing pressure to contain spending. The introduction of cash-limited, unified budgets and increased monitoring of prescribing within Primary Care Organizations (PCO) are intended to increase efficiency and enhance GPs financial responsibility. Whilst GPs regularly receive data on the costs of their prescribing and also performance against a set prescribing budget, little is known about the extent to which GPs take cost into account in their prescribing decisions. This study undertook a qualitative exploration of the attitudes of various stakeholders on the relative importance and influence of cost on general practice prescribing. In order to explore a plurality of perspectives, data were obtained from focus groups and a series of individual semi-structured interviews with GPs and key PCO stakeholders. The data suggest that although almost all GPs believed costs should be taken into account when prescribing, there was great variation in the extent to which this was applied and to how sensitive GPs were to costs. Cost was secondary to clinical effectiveness and safety, whilst individual patient need was emphasized above other forms of rationality or notions of opportunity costs. Conflict was apparent between a PCO policy of cost-containment and GPs' resistance to cost-cutting. GPs largely applied simple cost-minimization while cost-consideration was undermined by contextual factors. Implications for research and policy are discussed.