A process for preparing (+)duloxetine, or an acid addition salt thereof, which process comprises resolving racemic(±)duloxetine with a chiral acid so as to obtain a salt of the chiral acid and (+)duloxetine, substantially free of (−)duloxetine; and (ii) if desired, converting the salt prepared in step (i) to the free base or another acid addition salt as appropriate. The process for preparing (+)duloxetine, or an acid addition salt thereof, can further comprise an O-alkylation intermediate process step which is carried out in the presence of a base and a phase transfer catalyst.