Most countries in the world have very different love and marriage laws. These laws are often adjusted over time to match change in social values. Transformative trend of the past one hundred years has led to large changes in attitudes to love and marriage between contemporary society and earlier times. Marriage can be defined as a vow between two people to remain together as a couple. It has a civil form and a religious form. There is a great diversity of types of love and marriage, and social attitudes to some of them have changed greatly. In particular, attitudes towards cohabitation, gay and lesbian marriage and sole parenting were more accepted in the world. A cohabitation relationship can be defined as living together of two people as partners but without a marriage certificate. Gay and lesbian refers to marriage between people of the same gender. Sole parenting concerns a parent who is raising their children without a spouse.

One area of serious alteration is in attitudes towards cohabitation which has become more acceptable. In the past, cohabitation was considered to be shameful. However, today there are many people who live together as a couple without marriage. This is more popular in modern life than ever before. In Viet Nam for example, cohabitation is a new phenomenon in society over the last few years and has become a widely spreading trend. Viet Nam society used to base on Confucian values. Most children in the family were expected to live formally. Losing face or honour was the most important priority that people were concerned about in the past. For example, when a boy or a girl had sex before marriage. This was regarded as a stigma during their life. Similarly, cohabitation without marriage was viewed as shameful.

Compare to affluent society, cohabitation is becoming more acceptable. Because people are more open- minded. They want to