An analysis of ozone distribution in the atmosphericboundary layer based on monitoring data from two TORstations in Croatia is given. The levels were found tobe generally higher than expected for the continentalbackground. At the Puntijarka station, which can betaken as representative for the region, high valuesare mainly associated with transport from the west.The RBI station represents an urban site withoccasional photosmog situations. Short termmeasurements along the Adriatic coast have shown thatthere is a negative north to south gradient in ozoneconcentration as predicted by model calculations, butalso that some local photochemical production takesplace even at the remote Adriatic island far frompollution sources.