Any wealth tax design needs to resolve the question of who should pay it. How wide should the net be cast? Setting high or low exempt thresholds affects avoidance behaviour and may influence whether one should tax by reference to the household (and if so how that should be defined) or simply on each individual who owns wealth over a certain threshold. Typically, wealth taxes in other countries have not been imposed on non-residents except in relation to real property but questions remain over whether any exempt period should be given to new arrivals, not least for administrative convenience. A one-off wealth tax would require a different design in a number of respects from an annual wealth tax. For example, a one off tax would need to be designed to catch those who have recently left the UK and contain modifications for recent arrivals. Trusts, foundations and similar vehicles pose particular problems in the design of a wealth tax and the author suggests some possible solutions and connecting factors that could be considered.