"Blurred Lines" is an R&B song by Robin Thicke. It has vocals by Pharrell and T.I. and was produced by Pharrell. It was released on March 26, 2013. It was the lead single from his album "Blurred Lines". It has reached number one in 14 countries. It became Thicke's most successful song, being his first to reach number one on the Hot 100. He had already peaked number 14 in 2007 with "Lost Without U".