Spain in the Eurovision Song Contest 1973

Spain participated in the Eurovision Song Contest 1973 with the song "Eres tú" written by Juan Carlos Calderón and performed by the vocal group Mocedades. Televisión Española (TVE) selected internally both the song and the performer.

At Eurovision
Mocedades performed 7th in the night of the contest, following Monaco and preceding Switzerland. At the close of voting Mocedades had received 125 points, placing 2nd in a field of 17.

Congratulations: 50 Years of the Eurovision Song Contest
In 2005, "Eres tú" was one of fourteen songs chosen by Eurovision fans and a European Broadcasting Union (EBU) reference group to participate in the Congratulations anniversary competition. It was the only Spanish entry featured, as well as one of three entries featured that did not actually win the contest the year it competed (the others being "Nel blu, dipinto di blu" by Domenico Modugno and "Congratulations" by Cliff Richard). The special was broadcast live on La Primera of Televisión Española, with commentary by Beatriz Pécker and José María Íñigo.

"Eres tú" appeared fourth in the running order, following "Diva" by Dana International and preceding "Ein bißchen Frieden" by Nicole. Like the majority of entries that night, the performance was mostly by a group of dancers alongside footage of Mocedades' Eurovision performance, with the group themselves appearing toward the end of the performance (notably, appearing very moved at the warm reception they received from the audience in Copenhagen). At the end of the first round, "Eres tú" was not one of the five entries announced as proceeding to the second round. It was later revealed that the song finished eleventh with 90 points. In spite of this, it was also the only entry in the first round to receive multiple sets of twelve points without making it to the next round: one from the (where the song had charted at #3 in 1973) and one from Spain themselves, who had the opportunity to vote for their own entry. In the second round, without their own entry to vote for, Spain's twelve points were awarded to ABBA's "Waterloo," which ultimately won.