Consulting firm Mercer has released 2015's list of the world's most liveable cities. Vienna, Austria's elegant capital on the Danube river, has again been commended as offering the best quality of life of any city in the world, while Baghdad, once more, has been deemed the worst to live in. Europe has seven of the world's top ten cities in the 2015 survey, while New Zealand, Australia and Canada each have a city in the top 10. In Australia, the survey ranks Sydney as the Australian city with the best living standards. Other Australian capitals also ranked well with Melbourne at number 16, Perth at 22, Adelaide at 27, Canberra at 30 and Brisbane at 37. Mercer's survey helps companies and organisations determine compensation and hardship allowances for international staff. It uses dozens of criteria such as political stability, health care, education, crime, recreation and transport. Click here for the complete list.