OST composers usually look for singers who have previously had success in the genre. Songs are written to reflect the mood of the series and their structure. Sometimes performers give their own songs for a series. For example, Baek Ji-young thought her song "That Man", originally written for her own album, would fit "Secret Garden". There are popular OST singers who are often employed, like Baek Ji-young, Lyn, and Lee Seung-cheol. Sometimes, foreign singers are invited to perform songs for Korean OST. For instance, Swedish artist Lasse Lindh sang several songs for series like "Angel Eyes", "Soul Mate", "I Need Romance", and "".