This chapter explains the contemporary position of parental alienation in the family court systems in Australia and in the UK, primarily England and Wales. England (with Wales) and Australia are common law jurisdictions where the law about post-separation arrangements for children is found in legislation and interpreted by the higher courts. There is no reference to ‘parental alienation’ in any of our statutes and both jurisdictions encourage ongoing post-separation involvement of parents with their children. Discretion is given to judges, with the ‘welfare’ (UK) or ‘best interests’ (Australia) of children being the paramount consideration.