In The Reflexes of the Proto-Indo-European Laryngeals in Celtic , Nicholas Zair for the first time collects and assesses all the words from the Celtic languages which contained a laryngeal, and identifies the regular results of the laryngeals in each phonetic environment. This allows him to formulate previously unrecognised sound changes affecting Proto-Celtic, and assess the competing explanations for other developments. This work has far-reaching consequences for the understanding of the historical phonology and morphology of the Celtic languages, and for etymological work involving the Celtic language, along with implications for Indo-European sound laws and the Indo-European syllable. A major conclusion is that the laryngeals cannot be used to argue for an Italo-Celtic language family.