Groups reorganise for many reasons: simplification, regulatory compliance, and preparing a business for sale, to name a few. Business’ expectation will typically be that a group reorganisation carries no significant tax costs or risks. UK tax rules generally meet this expectation on reorganisations within the UK group – but there are a number of traps and anomalies in the detailed rules. While the tax department’s prime role is to advise on such risks, it typically plays a lead role in planning and executing the reorganisation. This plays to the tax department’s strengths, but care should be taken to co-ordinate the involvement of all relevant areas of in-house expertise, including finance, legal, HR and treasury.