H-Logic is the fourth studio album by South Korean singer Lee Hyori. It was released on April 12, 2010. The album has 14 tracks, including collaborations with Daesung from Big Bang, Jiyoon from 4Minute, Bekah from After School, Gary from Leessang, and Sangchu from Mighty Mouth. The singer worked also with E-Tribe, the team behind "U-Go-Girl", the lead single from her previous album. Following the album’s release, seven tracks from the album was revealed to be plagiarized by Bahnus Vacuum. After the controversy, Lee took a temporary hiatus until 2013.