The European Union Science Olympiad (EUSO) is a team competition for EU secondary school science students who are 16 years of age or younger. It was founded in 2002 by Mr. Michael Cotter. Apart from working as a lecturer at the Dublin City University, he is the President of EUSO, the Director of the Irish Science Olympiad and the treasurer of the International Board of the International Junior Science Olympiad. The first EUSO was held in Dublin, Ireland in 2003. Since then the competition has been held every year in one of the participating countries: 2004 in the Netherland, 2005 in Ireland, 206 in Belgium, 2007 in Germany, 2008 in Cyprus, 2009 in Spain, 2010 in Sweden and 2011 in the Czech Republic.The main objective of the EUSO is to challenge and stimulate gifted science students by helping them to develop their talents and promoting their careers as scientists. Not only is EUSO an occasion to meet for top science students from the European Union, it also fosters a positive and high profile image of science and scientists among the wider community.The students have the opportunity of enjoying a stimulating and varied cultural and social programme during their stay. Nonetheless, the competition is the main event of the Olympiad. The competition consists of two sessions during which the students work in teams of three on a specific subject. The tasks are designed so as to test their skills in tackling science problems and dealing with scientific experiments. A scientific jury, formed by the host country, elaborates the tasks. The student teams receive all tasks in their native language; the mentors are responsible for the translations.Luxembourg will participate with two teams (of 3 students each) at the 10th EUSO from the 22th to the 29th of April 2021 in Vilnius (Lithuania).