The paper surveys the plasticity of the speech production mechanism. At the level of phonatory behaviour, a distinction is made between the frequency of vocal fold vibration, which is reflected in the pitch of the voice, and the manner in which the vocal folds vibrate, which lends our voice different qualities. The main types of phonatory modifications are described and some of their uses in everyday communication, as well as their perceptual effects, are documented from literature. Modifications of the primary makeup of speech sounds in the supraglottal vocal tract, such as rounding or spreading of the lips, hyper- or hyponasality, and palatalization, are discussed in the following section. The two levels of description — phonatory and articulatory — are formally anchored in Nolan’s model of the sources of variability in speech. The final part of the paper examines speech variability from the perspective of the listener, regarding one’s speech as their auditory face which signals biologically, psychologically, and socially conditioned information about the speaker.