John Collier has been a supervisor, mentor, colleague and most importantly friend of mine for over twenty-five years. When he asked if I would like to do a new edition of his ‘magic book’, I did not hesitate. Although the last edition had been rather overtaken by the outpouring of new cases from the English courts and the CJEU, and the flood of new legislation from the European Union, it remained a book on my shelf to which I often turned for guidance. I hope to have maintained his clarity and brevity of expression as far as possible. I fear I may have failed his high standards in some places. Gender-neutral language has been used as far as possible, though I regret that occasionally that practice makes for less than fluent sentences. Regrettably, some of the chapters of the old work have had to be jettisoned. Important conflict of laws issues in succession, marriage and family law have been eclipsed in many courses in conflict of laws by the burgeoning and complex questions arising in jurisdiction, in choice of law in contractual and non-contractual obligations, and in property. Not only has there been a great deal of new EU legislation but the cases themselves have become more complicated and need more exposition to make them understandable. Judgments are longer. All of these factors have combined to militate against a shorter book. The interface between public international law and private international law and theoretical considerations in conflict of laws deserve whole books to themselves, which have already been written by people much better versed in the subject than I am. They too had to be excised. The chapter on domicile and habitual residence remains; partly as those concepts remain important in EU legislation and partly due to their inherent interest.