In Cistus ladanifer L. the chlorophyll (Chl) concentration differed widely along a latitudinal transect in the Iberian Peninsula [1.15-3.56 g kg-i(d.m.) and 146-655 mg m*2(leaf area)], and Chl a/b ratio and A43o/A^65 showed also a considerable variation (2.79-3.38 and 1.93-3.32, respectively). Chl content on a dry matter basis increased from the top to the base of the plant, especially in individuals with high leaf area index (LAI) values. Young leaves, situated in the periphery of the plant, had lower Chl content per leaf area and higher A43o/A^65 values than mature, more sclerophyllous leaves. Plants ffom higher altitudes, that suffered cold winters, showed generally lower Chl contents than plants from warmer sites. The Chl content and A43o/A^65 index were more sensitive to intemal and environmental changes than the Chl a/b ratio.