There is a clear need for the NHS hospitals to learn from medication errors to prevent future patient harm but this is hindered by an incomplete picture of the level and type of errors. The literature illustrates that the attitudes of health professionals to reporting incidents per se seem to be driven by negative attitudes about why they do not report (barriers) as opposed to positive attitudes about why they should report (benefits). The views of pharmacists are, currently, extremely poorly understood. A two part study was conducted with hospital pharmacists in the North West NHS region of England, including 4 focus groups (17 pharmacists) and 270 completed Theory of Planned Behaviourquestionnaires about the attitudes of hospital pharmacists to reporting medication errors.The study found that UK hospital pharmacists fully understood that it is part of their professional role to report medication errors and hold very strong intentions to report medication errors for the ultimate benefit of improved patient safety. They agreed with the four perceived barriers to the reporting of incidents by Health Professionals : Knowledge i.e. what to report, with the severity of the error most strongly influencing decisions to report or not; Effort i.e. difficulty in reporting, due to cumbersome forms and time/workload pressures; Fears, with the culture of blame still very much recognised by pharmacists and anxieties about reporting other health professionals due to close working relationships with medical and nursing staff; Outcomes i.e. lack of positive changes to prevent repetition of the error, with beliefs about the positive effects of reporting (increased awareness and reduced risk of similar harm) significantly predicting pharmacists' intention to report. Hospital pharmacists however also appear to have an additional fifth barrier to reporting, that is Size (of the problem). The "endemic" nature of medication errors means that hospital pharmacists, although resolving the errors, just do not report them as often as they would like, and know they should. Hospital pharmacists' intention to report medication errors was more likely if they were senior, or if they were female with strong beliefs that other pharmacists would similarly report the error.The key to improved reporting appears to be threefold: 1 Confidence -personal confidence to report health professional colleagues and overall confidence that positive outcomes will be seen from reporting. Though such cultural changes may be improved by greater hospital confidence in the benefits of reporting, and the introduction of measures to reduce harm, it is most likely this would require longer term organisational and professional cultural change; 2 Clarity - greater clarity about which medication errors should and should not be reported. Targeted reporting strategies could be introduced locally (e.g. cyclical reporting of one type of high risk medicine for 3 months) but might be more effective if implemented nationally, with a medication error reporting hierarchy comparable to the MHRA yellow card reporting scheme; 3 Simplicity - simpler drug specific reporting forms and assistance with the completion of the form by others e.g. a dedicated medication safety pharmacist. A national drive to allow hospital pharmacists to use a national medication specific, electronic error reporting form may further improve reporting.