The world's population has doubled over the past 50 years.1 The annual growth rate of 1.3% will result in a further increase to around 9 billion by 2050. Nearly a third of this growth is attributed to three countries in South Asia—namely India (21%), Pakistan (5%), and Bangladesh (4%)—which have historic, cultural, and economic ties with the United Kingdom. According to the International Organisation for Migration, the total number of migrants worldwide increased from 84 million in 1975 to 175 million by 2000,2 and by 2050 it may have reached 230 million.

Meanwhile, the global population of elderly people is increasing. By 2050 the overall growth rate of 2.4% per …