"There are cultural norms and attitudes that help get Asians to a certain level of success, but then work against them and hold them back from reaching a higher rank," Peck said. The challenges aren't insurmountable. Microsoft Corp. is led by an Asian CEO, Indian-American Satya Nadella, who has received high marks since taking the job 15 months ago. Another Asian leader, Sundar Pichai, has worked his way up to become one of Google's top executives since joining the company 11 years ago. In a Tuesday blog post that didn't directly address Ascend's report, Google said about half of its 55,000 employees have completed "unconscious bias" workshops as part of its diversity commitment. "With an organization of our size, meaningful change will take time," wrote Nancy Lee, Google's vice president of people operations. "From one year to the next, bit by bit, our progress will inch forward."