Citizenship involves both rights and obligations of citizens and states. There are various ways of acquiring citizenship, such as by birth in a country (jus soli) or descent from a citizen parent (jus sanguinis). The Philippines follows jus sanguinis, where citizenship is acquired from one's parents. Citizenship can also be acquired voluntarily through processes like marriage or naturalization. Citizens have duties like allegiance and defense of their state, while states have a duty to protect citizens. Dual citizenship is permitted but dual allegiance is discouraged under Philippine law.