This little paper is an excellent, if all too abbreviated, account of the elements of acoustic phonetics by one of the world’s foremost authorities on the subject. It covers the definition of phonemes and allophones, respectively the logical and acoustical units of speech; the basic facts about position and manner of articulation; and the notion of formants. It describes the acoustic parameters of speech, based on the series-formant model of Fant [1], and the use of sound spectrograms for speech analysis (with several examples). It is a skillful summary of some of the highlights of Ladefoged’s excellent book, A course in phonetics [2], first published 12 years ago. But rather than study this paper, readers interested in learning about phonetics would do better to give themselves a treat and spend an evening with the book itself, which is a delightful introduction to phonetics and highly relevant to computer speech processing.