Formant transitions from vowels into obstruents, or from obstruents into vowels vary in shape depending on the formant frequencies characteristic of the vowel and on the place and manner of the consonant. Human listeners appear to be able to use these formant transitions to identify the place and manner of the consonant, even when other aspects of the spectrographic pattern of the consonant are missing or ambiguous. But since the transitions are different in shape before different vowels (the formant trajectory must have one end rooted at the vowel formant frequencies), what is it about the transition that informs the listener about the consonant? The hypothesis is that it is the frequency that each formant transition is heading towards as a obstruction is made, or the frequency from which the transition comes as the obstruction is released that is important. This frequency seems to be characteristic of the consonantal place and manner, and appears to be roughly the same in different vowel contexts. Thus each formant for each consonant has a 'target' frequency which the listener can use to help identification of the consonant and which is the 'locus' of all formant transitions.