Although the tax system moved to independent taxation of married couples in 1990 many situations remain where a married couple is treated differently from two individuals for tax purposes. While the Government has legislated to place civil partners on an equal footing with married couples, there are considerable differences between the tax treatment of married couples or civil partners and unmarried couples. The introduction of tax credits based on joint assessment of couples and important case law developments in Human Rights, have left the overall situation increasingly confused and inconsistent. Different taxes - income tax, inheritance tax and capital gains tax - adopt different approaches to the taxation of couples. They adopt different approaches to the taxation of couples on separation, divorce or death. While each rule may be separately justified, no coherent structure to the arrangements emerges. The tax credit system has added a further layer of complexity and has focused attention on just how the family unit should be defined. The Project is carrying out a comprehensive review of these problems.