It is widely believed that there is a strong relationship between happiness and quality of life. This belief is supported by numerous studies which have found that happy people tend to have higher levels of income, health and social relationships than unhappy people. However, it is important to note that the relationship between happiness and quality of life is not always straightforward. While happiness may lead to improved quality of life in some cases, in other cases it may be the reverse. For example, people who are happiest during their retirement years may be those who had the highest quality of life prior to retirement.