Upon first glance, Islamic tourism seems only to cater for the needs of millions of Muslims around the globe who are performing hajj or umrah, visiting Mecca and Medina, or the shrines of Najaf and Karbala in Iraq. Yet in many ways Islamic tourism is lagging behind more conventional forms of international tourism and has yet to realise its fuller potentials. This article addresses the shariah concepts of halal and haram and their manifestations in the halal industry and tourism in two main areas: market developments of interest to halal tourism internationally and those that have taken place in Malaysia. Other topics discussed are ḥalāl certification procedures, the role of fatwas in the determination of halal, and more generally the return of Islamic values to the market place. The final segment of this article addresses the role of custom, culture, and religion as they are manifested in the behaviour of Muslim travellers and tourists.