Immigration points system begins BBC News Online An immigration officer at Heathrow Airport A long-expected overhaul of the UK's immigration system has come into force with the launch of a point-based system for foreign workers. The first stage of the system becomes operational on Friday - and will apply fully by the end of the summer. Ministers say the changes are the biggest for a generation - and will allow the UK to better control migrants from outside EU. But the Conservatives say they want an annual cap on the numbers allowed in. Under the system, migrant workers will need to show they have sufficient skills under new rules that assess whether or not the economy needs them. Applicants are given a score based on their abilities, with a special body advising ministers on how many points to award to certain skills to reflect economic conditions. The system is based on Australia's immigration rules and has been more than three years in the planning. It replaces a system of more than 80 categories that critics say was confusing, complex and failing to meet government goals. Five tiers The first of five tiers to come into force only affects highly-skilled people. At first those already living in the UK who want to extend their stay - 14,000 people last year - will be covered. The system will be fully in place for all highly-skilled workers by the end of the summer, says the Home Office. Points system explained Highly-skilled workers can apply to come to the UK without a job offer because they are considered to be among those most likely to benefit the economy. The category includes high-flying business people, entrepreneurs and scientists. Home Secretary Jacqui Smith said: "The introduction of our Australian-Style points system will ensure that only those with skills the country needs can come to work and study. "Today's proposals are part of the biggest changes to British Immigration policy in a generation, which includes a new deal for those migrants seeking citizenship here, a new UK Border Agency to strengthen controls at the border and the introduction of ID cards for foreign nationals." The next tiers to come into operation cover skilled workers who have a job offer, temporary workers and young people allowed to come in briefly. Businesses who want to bring in skilled workers from the autumn will need licences. Students will be covered from next year - but no date has been set for admission of low-skilled workers, largely affecting people from poorer parts of the world. The government has also introduced new fines found to be employing illegal immigrants. The points-based-system does not cover workers from Eastern European nations which have joined the EU in recent years. These workers, along with British people, have freedom of movement around the union.