Khat, the leaves of Catha edulis Forsk. (Celastraceae), is widely used as a stimulant in East Africa and the Arab Peninsula. Samples from the most important markets of Ethiopia, Kenya, North Yemen and Madagascar were analysed with high-performance liquid chromatography (HPLC) concerning their khatamine content (phenylpropyl and phenylpentenylamines). The variability of khatamines depending on origin, type and quality is discussed. In many samples a good correlation between the amount of cathinone, the main CNS-active compound, and quality estimation (price) of dealers and consumers was found.