The delineation of constituencies is a major duty of the Electoral Commission.
An Electoral Commission is a body of persons which is created by law in a state. It is given the responsibility of organizing and conducting free and fair elections in the state. e.g Federal Electoral Commission (FEDECO). National Electoral Commission of Nigeria (NECON) Independent National Electoral Commission (INEC).
Some of its functions are as follows:
1. It divides the country into electoral dictrists called constituencies.
2. It registers political parties
3. It sees about registration of voters, compilation of voters register and revision and updating of voters' register.
4. It provides election materials e.g Pencil voters' registers, ballot paper and boxes, etc.
5. It appoints and train electoral officers e.g prisiding and returning officers, counting officers etc.
6. It announces the results of elections etc.