Researchers often view the production of P-values as an essential component of statistical analysis. But in recent years many statisticians and epidemiologists have become increasingly disillusioned with P-values. Wrong beliefs about P-values, and wrong interpretations of P-values, are encountered on a daily basis. Mis-interpretation of P-values is contributing to the reporting of non-reproducible research results. P-values were the subject of a recent debate at a School of Population Health and Environmental Sciences seminar. Abdel Douiri and I spoke about P-values. There was also a lively exchange of views among those present.