For an alien to become a citizen of a country, he/she must meet certain conditions as stipulated by the constitution of that country.
In Nigeria for instance, the acquisition of citizenship by registration and naturalization are dependent upon the meeting of the following conditions as stipulated by the constitution of the Federal Republic of Nigeria:
- The alien must be a person of full age (18) and capacity.
- He must be a person of good character.
- He must show a clear intention of his desire to be domiciled in Nigeria.
- He is, in the opinion of the governor of the state where he is or he proposes to be a resident, acceptable to the local community in which he is to live permanently and has been assimilated into the way of life of Nigerians in that part of the federation.
- He is a person who has or is capable of making useful contributions to the advancement, progress and well-being of Nigeria.
- He has taken an oath of allegiance prescribed in the sixth schedule of the constitution,
- He has resided in Nigeria for a continuous period of fifteen years.
- The individual’s good behaviour must be attested to by an individual already a citizen of the country.