1. Born in the country. 2. Parent or grandparent born in the country. 3. Three years uninterrupted residency immediately prior to selection. However, it's not necessary to go through a legal naturalization process under this rule. 4. HAVE NOT ever been capped by a 1st or 2nd level senior 15s or 7s squad. 2nd level squads are those like the Saxons (England), Wolfhounds (Ireland), or Jaguars (Argentina).
Genrally to be born there or have a parent or grandparent born there. As well, you may be able to take out citizenship of that country but if you have played for one country, you can't play for a second.