22.The commentary uses a number of abbreviations. They are listed below.
| CAA | the Capital Allowances Act 2001 |
| CAA 1990 | the Capital Allowances Act 1990 |
| CRCA | the Commissioners for Revenue and Customs Act 2005 |
| ESC | Extra-statutory concession |
| HMRC | Her Majesty's Revenue and Customs |
| FA 1989 | Finance Act 1989 (and similarly for other Finance Acts) |
| F(No 2)A | Finance (No 2) Act |
| FISMA | the Financial Services and Markets Act 2000 |
| ICTA | the Income and Corporation Taxes Act 1988 |
| IHTA | the Inheritance Tax Act 1984 |
| ITA | the Income Tax Act 2007 |
| ITEPA | the Income Tax (Earnings and Pensions) Act 2003 |
| ITTOIA | the Income Tax (Trading and Other Income) Act 2005 |
| NIC | national insurance contributions |
| PAYE | Pay As You Earn |
| R&D | research and development |
| TCGA | the Taxation of Chargeable Gains Act 1992 |
| TMA | the Taxes Management Act 1970 |
| VAT | value added tax |