In this study, the (ZD)EopDD bleaching sequence for a softwood pulp was compared with the conventional ECF reference sequence DEopDD used in the mill. A Pinus radiata kraft-oxygen pulp was treated with a (ZD) stage at 0.3% ozone and 0.5% chlorine dioxide charges. The best result was reached with the (ZD) process when O3 and ClO2 were added sequentially at high consistency. The use of ozone allowed a 43% reduction in the use of chlorine dioxide. With the (ZD)EopDD sequence a 90%ISO brightness bleached pulp was obtained, having acceptable mechanical properties, which are comparable to that generated by the DEopDD s