Not only are U.S. workers happy with their jobs, but they also give high marks to their bosses. Managers were evaluated on their ability to communicate, delegate responsibilities, generate a team spirit and exert leadership. On a scale of 1 to 10, employees in the U.S. gave an average rating of 7.3 to their bosses. That mark is only second to the 7.6 that Mexican workers give to their supervisors.

But there is still room for improvement. The levels of happiness among workers varied according to industry. Only 37 percent of respondents who work in retail, for example, say they are happy with their job. There are other areas of concern as well. Almost 30 percent of workers say they are rarely or never rewarded for a job well done.

“The challenge is to continually provide interesting and meaningful work as well as opportunities for employees to learn and more fully develop their own skills,” says George Corona, senior vice president at Kelly.

The results of the Kelly survey provide a refreshing change from other studies, which depict a much more depressed, unhappy and unengaged workforce. Sibson, a human resources consulting firm, released a study last month indicating that workers are less satisfied and less engaged. According to the report, career satisfaction dropped from 61 percent in 2003 to 41 percent this year.

The Kelly and Sibson surveys don’t use the same yardstick to measure results, but the divergence in their findings could make it confusing for employers to trying to understand the psychology of their workforce. Regardless of whether a survey portrays a workforce that is happy or one that is not, what's important is for employers to strive toward enhancing practices that are known to make a positive difference in the workplace, Corona says.

“Time and again, workers tell us that they want a workplace with good morale, stimulating work, a degree of autonomy and meaningful feedback from their bosses,” he says.

--Gina Ruiz