In the category of what has changed significantly about marriage in the 21st century, add the fact that more couples are eschewing joint bank accounts and electing to keep their finances separate.

Sociologists and others who study this sort of thing site numerous reasons why Millennials are electing to keep money separate after marriage. For starters, couples are waiting longer to get married, which means individuals have established themselves in terms of career and salary. Letting go of financial independence can be tough after you’ve had it for a decade or more.

Financial Independence = Self-Identity

Atlantic writer Caroline Kitchener says when she asked married couples why they kept their finances fully or partially separate, the most common answer was to maintain a sense of identity. Women, particularly, do not want to lose control of their financial lives. ““My clients want to make sure they never end up in a situation where they don’t know what is going on,” Maggie Germano, a women’s financial coach based in Washington, D.C., told Kitchener.

Relationship counselors and other professionals have mixed feelings about the fallout of this trend. A director of a marriage project who Kitchener spoke with pointed to a study from 2006 that showed couples who merge their finances are more likely to remain together because they build trust. Another specialist, however, questioned the validity of the 12-year-old study since Millennials are drastically different than the generation ahead of them. Indeed, many couples that Kitchener spoke with argue that keeping separate bank accounts is a sign of deeper trust in each other.

Communication Is Key

Differences over finances are a top marriage killer. Whether spouses combine finances or keep them separate, the key is to communicate often and honestly about the money decisions being made in the household.

It certainly makes sense to discuss financial personalities before marrying. Such a discussion may lead to a couple deciding that a prenuptial agreement will help make the marriage stronger.