The Iban customs and traditions (adat) have been created or prescribed for the pursuance of societal survival and continuity.

“Custom” is defined as tradition, observance, convention, manner, etiquette, ritual, habit, practice, rite, ceremony, wont and rule. “Tradition” refers to custom, institution, convention, ritual, way of life and habit. Tradition includes oral tradition which encompasses the full range of meaning by which Ibans construct social memory, which includes Iban narratives, myths, legends, verbal songs, magic, rituals, ritual speeches, poetry, epic, laws, dances, traditional music, genealogies, stories of old, sacred places, poems of lamentations, boundary marking and augury. It concerns the way Ibans collectively remember their past and make it relevant to the present.

ADAT is, therefore a way of life, basic values, culture, accepted code of conduct, manners and conventions. These broad definitions include aspects of law, moral, religion, custom, habit, etiquette, agriculture and fashion that must be adhered to in order that the Iban could live harmoniously and obtain the favour of the gods.

In Sarawak, only some of the customs and traditions of the Ibans have been codified in the ADAT IBAN 1993.

As such, the ADAT IBAN 1993 is not exhaustive of the Iban Adat. The legislative definition of ‘native customary law’ treats customs, traditions and adat as synonymous.