Spectrographic data show effects of both initial and postvocalic /l/ upon average vowel formant frequencies. The present study investigated preference judgements for F 1 and F 2 in three vowels in /l/ context. Subjects were asked to choose the vowel of a pair that was more similar in quality to a preceding isolated vowel. Significant preferences were obtained chiefly on vowels preceding /l/ and only for F 2 variations. A supplementary experiment showed poor discriminability of contextual differences in both F 1 and F 2 values during /l/ steady states. The data were interpreted as favourable to the proposition that perception can solve the problem of coarticulation in at least two different ways—by modelling it in detail (weak form of motor theory) or by applying an information-losing categorical strategy.