chapter 1 Introduction -- chapter 2 Why voices are difficult to discriminate forensically -- chapter 3 Forensic-phonetic parameters -- chapter 4 Expressing the outcome -- chapter 5 Characterising forensic speaker identification -- chapter 6 The human vocal tract and the production and description of speech sounds -- chapter 7 Phonemics -- chapter 8 Speech acoustics -- chapter 9 Speech perception -- chapter 10 What is a voice? -- chapter 11 The likelihood ratio revisited: A demonstration of the method -- chapter 12 Summary and envoi.