At the center of most towns is a market place ( sug ), the lanes of which are lined with open-front booths where food and implements are displayed and sold. Some goods are bartered. Others sold for cash, usually after bargaining. The production of qat , a mild stimulant which many Yemenis chew, plays an important role in domestic trade. Relying on a highly sufficient internal distribution system, the production of qat would increase per capita GDP an estimated 15–20% were it included in the national income statistics. Corruption among civil servants is a common element of domestic commerce—soldiers at checkpoints confiscate money or qat , and businesses are often obliged to pay off local officials.
Customary business hours are from 8 AM —1 PM and from 4 PM —7 PM , Saturday–Thursday. Banks are open from 8 AM —12 PM (11:30 AM on Thursdays).