Making sure domestic law works as we leave the EU will be a substantial challenge for both Government and Parliament in complexity and planning to deal with a number of scenarios. In the previous two Parliaments, an average of 1,338 (2005-10) and 1,071(2010-15) statutory instruments were made per year. ¹¹ A proportion of this secondary legislation, as it has been every year, was implementing EU law. We currently estimate that the necessary corrections to the law will require between 800 and 1,000 statutory instruments. This is in addition to those statutory instruments that will be necessary for purposes other than leaving the EU. Ultimately though, it is not possible to be definitive at the outset about the volume of legislation that will be needed, as it will be consequent on the outcome of negotiations with the EU and other factors.