This paper examines variation in rim diameters in order to assess the amount of standardization evident in pottery production at the Islamic site of al-Basra in northern Morocco. The study shows that storage jars made primarily in the early period at the site exhibit relatively higher coefficients of variation than vessels made during the last two periods, suggesting that the early assemblage was produced by less skilled artisans or by more potters. A comparative study of pottery from two Roman sites in Libya (Cyrenaica) and two contemporary villages in the Philippines indicates that the early Moroccan pottery may have been made by part-time specialists.