Goodbye Lullaby is the fourth studio album by Canadian singer-songwriter Avril Lavigne, her last to be released by RCA Records. The album was first released on 2 March 2011, four years after the release of her earlier album The Best Damn Thing. Recording sessions began in November 2008, and took place over a period of almost two years, concluding in October 2010. The album's songs contain mainly stripped down instruments, such as the piano and acoustic guitar. Every song on the album was written by Lavigne, with half of the album being written with co-writers.