International evidence suggests clearly that increases in capital gains taxes above a very modest level result in decreases in revenue. Similarly, if capital gains tax rates are set above a relatively modest level, then their reduction will involve an increase in revenues. This paper uses new evidence from Ireland, Sweden and Switzerland combined with existing analysis from America, Australia and Britain to try and identify more precisely the revenue consequences of CGT increases in the UK. It looks at both revenue losses from capital gains tax and from other taxes.