An analysis of the connection between Islamic law (sharīʿa) and custom (ʿurf), identifying the ways in which personal and social issues are treated within contemporary Saudi and Iranian legal approaches. Approaches adopted by Saudi-Ḥanbalī and Iranian-Jaʿfarī scholars towards the sharʿī status of ʿurf in three particular categories are examined; the methodological perspective (classic and contemporary), the sharʿī opinions of scholars (fatwā) and the court verdicts of judges (aḥkām). The interaction between custom and textual authority is emphasised, developing an analytical framework of shar‘ī rules that pertain to social relations in general and marital issues in particular.