Because it has been suggested that both the frequency of deliberate self-poisoning and the characteristics of those who self-poison differ between Ireland, and England and Wales on the one hand and Denmark on the other we have examined self-poisoning rates and suicide rates in these three countries. Higher self-poisoning rates were found for England and Wales than for the other two countries below age 35. After this age self-poisoning rates decline in both England and Ireland but female rates continue to rise in Denmark up to age 45. Danish suicide rates are conspicuously higher than those of both England and Wales, and Ireland. Because combined death rates for suicide, undetermined and accidental deaths diminish but do not remove the differences between countries it is suggested that the Danish suicide death rate reflects a genuinely higher rate of suicide in that country.