The main object is to discuss principles and therefore many points of detail will be omitted, however intrinsically interesting they may be. Satisfactory consideration of principles entails reference to all classes of business which involve an actuarial valuation (viz. life assurance and annuity business, sinking fund business and permanent sickness insurance business). Reference will be made to the National Defence Contribution and the Excess Profits Tax, which are based upon income-tax legislation. The subject in mind is the relation of such taxation to insurance business and funds of the classes mentioned, as distinct from other aspects of income tax which an insurance office encounters, and it will be considered solely from the point of view of an office established in the United Kingdom which transacts business only in the United Kingdom. In view of the paper by Messrs S. J. Rowland and F. H. Wales on ‘The Taxation of the Annuity Fund’ (March 1937, J.I.A. Vol. LXVIII), only brief reference will be made to annuity business, and it will be assumed that it is unnecessary, in describing taxation processes, to include explanations or qualifying phrases on account of annuity business.