Jane Passy's highly successful technique first came about through her work with children with severe speech and language disorders. Each of the 49 sounds (phonemes) that make up the English phonological system has a separate hand sign - related to where and how, in the mouth, the sound is made. The signs are logical and based on sound linguistic theory. The consonant sounds are colour-coded as an extra visual cue when doing written work. Cued Articulation and Cued Vowels are two companion texts written by Jane Passy to help teach the pronunciation of spoken English. Cued Articulation describes how to cue consonant sounds while Cued Vowels describes the 23 standard English vowel sounds.