The UEFA European Under-19 Championship consists of three distinct stages: the qualifying round, the elite round and the final tournament.
The qualifying round, played in autumn, is made up of 13 groups of four teams playing in one-venue mini-tournaments. The top two from each progress.
In the elite round, played in the spring, those 26 qualifiers join the top two seeds, given a bye, in seven mini-tournament groups of four. The group winners then join the hosts in the finals.
The seven qualifiers plus the hosts are split into two groups of four who play each other once, with the top two progressing to the semi-finals. The winners of those ties contest the final.
Further details, including the criteria for separating teams that finish level on points in a group, or after extra time in a match, can be found in the official competition regulations.
By Andrew Haslam in Belfast
The UEFA European Under-19 Championship finals in Northern Ireland represent a first opportunity for many players to experience a major international competition, and the same is true of the six referees and eight assistants who make up the team of match officials.
The referees are all in categories two and three of the UEFA list, and one such official is Alberto Undiano Mallenco, who is thoroughly enjoying his first big tournament. "Everything has been really great for me so far," he told uefa.com. "We arrived on Saturday before the tournament started, and everything has run smoothly. It's been impeccably well organised by UEFA and the local organising committee."
'Newry is nice'
The 31-year-old Spaniard has been based in Newry for the group stage, taking charge of the matches between Serbia and Montenegro and Germany in Group A and the decisive Group B encounter between England and Norway. He also acted as fourth official on Matchday 2 when Northern Ireland met Serbia and Montenegro. Undiano is certainly happy with the arrangement, saying: "I think Newry is a very nice place, the spectators are close to the pitch and I have enjoyed the matches very much, the atmosphere has been perfect. The players behaved well, and everything went well."
The Pamplona-based official is keen to take in as much as possible, adding: "This is a big step forward for me. The organisation is superb and the players and officials both have more responsibility as this is a European Championship finals. I am learning many things here, as there are referees from all around Europe here and we can share ideas and improve our standard.
"There are many good referees and assistants here and UEFA has a lot of experience so you can really improve. I'm improving because, in all matches, you get various different situations to deal with and UEFA is really good at giving you tips on how to cope with these. A lot of it comes down to experience, which teaches you how to deal with new situations."
Undiano knew from an early age he wanted to be an official. "I started my career as a referee when I was 13, which is very young. I played football, but I was very bad, so I decided to become a referee. In the beginning, it was a hobby - I enjoyed it very much but never dreamt I could make it my career. But, with much work, I have progressed. I've worked hard and always tried to improve and learn from my mistakes. If you think you are a perfect referee, soon your standards will start to slip."
Undiano will have another special reason to remember this tournament, as his wife gave birth to their first child, David, last Saturday while he was travelling to Northern Ireland. "It was a little strange for me as I left home and two hours later, my wife called to say she had to go to the hospital.
"I was a little nervous as I was flying all day, but when I arrived here my wife's sister called me to say everything was OK and to stay and enjoy the tournament. It's still a little strange as obviously I would like to be with my wife at this time. But I understand that many others have this problem, and when I get home, I will have lots of time to spend with my baby."
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