The paper reports the results of an experiment designed to explore the interaction between tone and quantity in Serbocroatian. The test materials consisted of 39 synthesized versions of the test word pusti. Depending on the type of accent, this word may have four meanings, short accents being associated with forms of the verb pustiti and long accents with forms of the adjective pust. In producing the test stimuli, the duration of the first vowel was varied in 10-msec steps from 120 to 240 msec. Three fundamental frequency patterns were superimposed on the test words: a monotone pattern, a falling pattern, and a rising pattern. Twelve listeners identified the stimuli as forms of the verb pustiti or of the adjective pust. The results indicate that the tonal patterns influence the boundary value at which listeners change from ‘short’ responses to ‘long’ responses. This boundary value was at 145 msec for monotone and falling fundamental frequency patterns, and at 170 msec for words with rising fundamental frequency patterns. The responses are interpreted with reference to the dialect background of the listeners: the higher crossover point between short and long rising accents appears to be a characteristic of listeners from Vo