This paper considers the advantages and disadvantages of introducing a net wealth tax in the Republic of Ireland. The implications for vertical and horizontal equity are discussed, as are the implications for economic efficiency, growth, savings and potential capital flight. There are other major questions. Are there administrative barriers to its introduction? How should debt be treated? Who should pay the tax? How does the tax relate to other taxes? How should assets be valued? The key objectives of a net wealth tax are to raise a meaningful amount of revenue for the exchequer and improve horizontal and vertical equity while at the same time minimising administration and compliance costs, minimising economic distortions, and minimising the risk of capital flight. The tax structure most compatible with these policy objectives is one with either zero or very few exemptions and reliefs, a high threshold of liability, and a flat marginal rate that is set at a low level. Nevertheless, for practical reasons it would be necessary to exempt certain asset classes, for example human capital. There is a general lack of good data on the distribution of wealth in Ireland and the potential revenue yield from a net wealth tax is highly dependent on the degree to which wealth is concentrated in the right hand tail of the population. Even so, a yield of at least 0.1 per cent of GDP appears very much compatible with a threshold of liability for net wealth set at €1 million and a wealth tax rate set at 0.6 per cent. Such a yield is attainable even under very conservative assumptions of aggregate wealth and the distribution of wealth in Ireland. Less conservative assumptions of the degree to which wealth is concentrated in the top 1 to 2 per cent of the population generate substantially higher estimated yields.