Centrally located secondary carotenoids, mainly astaxanthin, disperse towards the periphery of Haematococcuslacustris (Chlorophyta)cells under light induction, and move back towards the centre after illumination is discontinued. Absorption spectra and HPLC analysis of the extracted pigments show no major quantitative or qualitative changes during this migration, indicating that the dispersion effect is due to relocation of the existing pigments under the influence of light. Red akinetes (non-motile cells filled with secondary carotenoids) are found to be more resistant to photoinhibition than green akinetes. A possible photoprotective role for the secondary carotenoids is therefore suggested.