Managers agree that favouritism is a big factor in deciding who gets promoted although not many will admit to being biased in any way.

A survey by Georgetown University's McDonough School of Business and research firm Penn Schoen Berland has found that 84% of business leaders admit to favouritism at their workplace. However, only 23% acknowledged practicing it themselves. A mere 9% said it was a determining factor in their last promotion.

This figure of 9% was higher than what the author of the study had expected. "No one at this level of executive was going to admit it blatantly," Jonathan Gardner said.

Although three-quarters of survey respondents said that there are procedures in place to ensure fairness in the workplace, there are other subjective criteria such as whether the candidate "fits" into the corporate culture which make the lack of prejudice highly questionable.

Productivity and morale can suffer because of favouritism. "They're now playing office politics instead of focusing on organisational objectives," Lamar Reinsch, a management professor at McDonough and Gardner's advisor on the paper, was quoted as saying in the Wall Street Journal.

Locally, companies like Citi have been tackling unconscious bias head on. "Addressing unconscious bias is a diversity initiative for many companies and one of the hardest to tackle," said Joanne Allen, head of human resources for Citi in Australia and New Zealand. "However if we are to create a truly inclusive workplace it's an area our managers need to understand and manage," she said.

Diversity plans at Citi in 2011 include a focus on manager accountability and education. This will include training to address unconscious bias, build an engaged workforce, and redesign jobs to support flexible work arrangements. "Managing unconscious bias has become a popular training program in the financial services industry," said Allen. "Behavioural psychology tells us that even the most open-minded individuals have unconscious biases. It's important managers understand these and ensure they are not making decisions or creating processes based on over-generalisations or wrong assumptions."