Luxembourg was represented by French singer Anne-Marie David, with the song '"Tu te reconnaîtras", at the 1973 Eurovision Song Contest, which took place on 7 April in Luxembourg City following the victory of Vicky Leandros for the Grand Duchy the previous year in Edinburgh. The song was chosen internally by broadcaster RTL and went on to bring Luxembourg their second consecutive Eurovision victory and a fourth in total.

Following the contest David recorded "Tu te reconnaîtras" in various languages and enjoyed a sizeable hit in many parts of Europe. The English-language version of the song ("Wonderful Dream") went to number 13 on the UK Singles Chart.

On the night of the final David performed 11th in the running order, following Italy and preceding Sweden. Pre-contest betting had rated the entries from Spain and the United Kingdom as favourites, with Luxembourg some way behind. The same voting system used in the previous two contests was used again, but whereas the 1971 and 1972 contests had both produced very clear winners, in 1973 the voting was very tight throughout. After the votes from the fourth of six groups of voters, the United Kingdom was ahead of Luxembourg and Spain by 3 points, but Luxembourg scored strongest from the last two groups and gained a narrow victory, 4 points in front of Spain and 6 ahead of the United Kingdom. The closeness of the result, together with complaints which had been made from the start about the system's potential for manipulation – it was the only system ever used in which countries did not all have the same preset amount of points to award – led to the abandonment of the system before the 1974 contest.

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