“Stress levels are at an all-time high, work hours are at an all-time high and employer tolerance is high,” said Mark Oldman, a Vault founder. “With so much of our lives based in the office, there’s a certain inevitability of amorous situations developing at the watercooler and beyond.”

Demographic changes to the workforce also have a big effect. About 46 percent of today’s workforce is female, compared to 31 percent a half century ago, according to the Bureau of Labor Statistics. And the number of single people in the workforce has increased 18.3 percent in the past 10 years, according to a 2005 analysis of unpublished Bureau of Labor Statistics data by global outplacement firm Challenger, Gray & Christmas.

In addition, people are focusing on their careers and getting married later in life. According to the U.S. Census Bureau, the median age at which people first get married is 25.3 years for women and 27.1 for men, up about four years in the past three decades for both groups.

E-mail has made office flirtation convenient and seemingly private. Add to that frequent business trips with colleagues, after-work drinks, and the connections made by sharing interests, frustrations and successes, and the workplace becomes ripe for romance.

“Nowadays, people don’t go out and connect with organizations and communities like they used to,” said John A. Challenger, chief executive officer of the outplacement firm. “They’re alone in front of their TVs and computers until they return to work. The workplace has become the prime meeting ground.”

READ: Once taboo, office couples are more commonplace

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