The right to stand for election may be subject to the support either of a certain number of electors to exclude frivolous candidates, which is acceptable if the number is sufficiently small, say single figures in a single seat system and a few dozen in a list system, or of a political party. The latter is more complex and raises the question of political parties' recognition and their selection procedure, for example whether this is in the hands of the leadership, the various party bodies or the membership as a whole, or – as seems to be a growing trend – is based on a primary elections system. This is dealt with in the Venice Commission's Code of Good Practice in the field of Political Parties, but it has to be pointed out that for individuals the need for party support is the main restriction on election to parliament because without the investiture or support of a party of a certain size the chances of success are very limited, even if individual candidatures are possible.