Gaynor Sullivan (née Hopkins; born 8 June 1951), known professionally as Bonnie Tyler, is a Welsh singer who is known for her distinctive husky voice. Tyler came to prominence with the release of her 1977 album The World Starts Tonight and its singles "Lost in France" and "More Than a Lover". Her 1977 single "It's a Heartache" reached number four on the UK Singles Chart, and number three on the US Billboard Hot 100.

In the 1980s, Tyler ventured into rock music with songwriter and producer Jim Steinman. He wrote Tyler's biggest hit "Total Eclipse of the Heart", the lead single from her 1983 UK chart-topping album Faster Than the Speed of Night. Steinman also wrote Tyler's other major 1980s hit "Holding Out for a Hero". She had success in mainland Europe during the 1990s with Dieter Bohlen, who wrote and produced her hit "Bitterblue". In 2003, Tyler re-recorded "Total Eclipse of the Heart" with singer Kareen Antonn. Their bilingual duet, titled "Si demain... (Turn Around)", topped the French charts.

Rocks and Honey was released in 2013 and features the single "Believe in Me", which she performed representing the United Kingdom at the Eurovision Song Contest 2013 in Malmö, Sweden. After reuniting with the producer David Mackay, she released Between the Earth and the Stars (2019) and The Best Is Yet to Come (2021).

Her work has earned her three Grammy Award nominations and three Brit Award nominations (including twice for British Female Solo Artist), among other accolades. In 2022, she was awarded an MBE in the Queen's Birthday Honours for services to music.