Some of the most famous rules in a popular dating guide say "No more than casual kissing on the first date" and "don't rush into sex, wait at least three dates."
But a new study has suggested that such a regimented guide to dating and romance should be thrown away, insisting that casual sex can in fact lead to a meaningful relationship.
The study at the University of Iowa also revealed that living together before marriage is not a bad idea.
The Rules, Ellen Fein and Sherrie Schneider's 1996 seminal guide to dating, has become a way of life for many women dedicated to snagging Mr Right.
However, Dr Bethany Marshall, author of Deal Breakers: When to Work On A Relationship and When to Walk Away, said that those women and men who follow regimented rules may have got it wrong.
"Playing by specific rules can make you less likely to pay attention to your own inner voice and experiences," News.com.au quoted Dr Marshall as telling Women's Health.
Anthony Paik, an assistant professor of sociology also added, "People now view hooking up as a predictable, normal part of life and don't let it contaminate or poison the beginning of a relationship."
The study found that "a significant percentage of current relationships began with non-romantic sex."
Another of the key Rules says "Don't live with a man (or leave your things in his apartment)."
But the National Centre for Health Statistics claims cohabiting before marriage does not affect the chances of a successful and happy union.