"Lo Mejor de Tu Vida" ("The Best of Your Life") is a ballad written and produced by Spanish singer-songwriter Manuel Alejandro, co-written by Marian Beigbeder, and performed by Spanish singer Julio Iglesias. It was released as the first single from his studio album Un Hombre Solo in 1987. The song became the first by a male performer to spend 13 weeks at number one in the Billboard Hot Latin Tracks chart and held the record for the biggest leap to the top of the chart for over twenty years (from 14 to 1) until Mexican rock band Maná leapt from 22 to number one with "Manda Una Señal" in 2007.

"Lo Mejor de Tu Vida" is also recognized as one of Iglesias' signature songs and has been covered by several singers, including Tamara, Simone, Ray Conniff, Bertín Osborne and Alexandre Pires.

Julio Iglesias was the most popular Latin singer of the 1970s and 1980s, selling over 100 million albums around the world. In 1968, he was a contestant at the 1968 Spanish Song Festival at Benidorm, singing his original song "La Vida Sigue Igual". Iglesias won the first prize at the contest, which led to a record contract with Columbia, an independent record label. During the 1970s, he toured Europe and Latin America, gaining a large fan base with hits like 1975's "Manuela", written by Manuel Alejandro. A few years before, Iglesias was watching another performer during a music festival and thought that the song he was singing was beautiful, began asking who was the writer of the track, and someone told him that the songwriter was Manuel Alejandro. Iglesias refers to Alejandro as the "greatest Spanish songwriter in history." Alejandro and Iglesias worked together again on Un Hombre Solo which was awarded the Grammy for Best Latin Pop Performance and sold three million copies worldwide. Manuel Alejandro said to the Spanish newspaper La Revista that Iglesias was the best performer of his songs, and praised the simplicity of his work.

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