Nationality and Cases of Statelessness in the Middle East and North Africa demonstrates these challenges where an incomplete census exercise which left a large number of people unregistered and undocumented subsequently influenced who was recognised as meeting the criteria for the enjoyment of Lebanese nationality, thereby leaving many thousands stateless. Over time, this statelessness has become a protracted and inter-generational problem for many in Lebanon, despite various initiatives to reduce the numbers.68 This illustrates how critical it is to prevent statelessness from arising in the first place, given how enduring its effects can be. Additional and alternative eligibility criteria may be set alongside residence requirements for a person to be admitted as a national with the coming into force of the country’s first nationality law. In Libya, for instance, in addition to having been resident on the 7th of October 1951,69 acquisition of Libyan nationality was also conditional either 10 years residence on that date, or birth on Libyan soil, or birth abroad but to a parent who was born on Libyan soil. While this residence period is shorter and therefore potentially easier to establish, there may still be similar challenges in practice with regard to proof of residence and/or, in this case, proof of place of birth. Moreover, where 68 - See further chapter 3. 69 - The date of entry into force of the country’s constitution. 58