Pet Shop Boys are an English synth-pop duo formed in London in 1981. The group consists of keyboardist Chris Lowe and vocalist Neil Tennant. They have sold more than 100 million records worldwide and were listed as the most successful duo in UK music history in the 1999 edition of The Guinness Book of Records. The duo has achieved 42 top 30 singles, including 22 top-10 hits on the UK singles chart, with four UK number-one singles: 'West End Girls', which also reached number one on the US Billboard Hot 100, 'It's a Sin', a synth-pop version of 'Always on My Mind', and 'Heart'. Their other notable songs include a cover of 'Go West', as well as 'Opportunities (Let's Make Lots of Money)' and 'What Have I Done to Deserve This?', a duet with Dusty Springfield. During the 1980s, they had five US top 10 singles and are associated with the Second British Invasion. The Pet Shop Boys have been nominated for four Grammy Awards in the Dance/Electronic categories and have won three Brit Awards. They received the Brit Award for Outstanding Contribution to Music in 2009.