A study of chlorophyll and carotenoid composition of nine singlevariety virgin olive oils from the main Spanish producing regions has shown differences depending on variety and ripening degree of the fruits. Pheophytin a was the major pigment in all the oils studied (44-58% total pigments), followed by lutein (18-38%) and 8-carotene (6-17%). The chlorophyll pigments group also included pheophytin b and in some cases chlorophylls a and b. The carotenoid fraction also included the xanthophylls neoxanthin, violaxanthin, luteoxanthin, antheraxanthin, mutatoxanthin and 8-cryptoxanthin. The mean provitamin A activity of the oils was 260 pg kg-expressed as retinol equivalent. cis-a-Carotene (tentative), mono-and di-esterified xanthophylls and pheophorbide a were pigments exclusive to Arbequina variety, a fact that could be used as a chemo-taxonomic differentiator of the oils of this variety. The ratio between the chlorophyll fraction and the carotenoid fraction was maintained in most cases around 1, demonstrating that the green and yellow fractions were in balance, notwithstanding their greater or lesser total pigment content. The considerable range in the lutein/b-carotene ratio (between 1.3 and 5.1 depending on variety) makes this ratio a differentiator of single-variety oils. Despite the different sources of the oils, some general trends have been shown which suggest what chlorophyll and carotenoid pigments should be expected in an olive oil so as to include it within the denomination 'virgin'.