This paper will discuss the dual nature of sound and explore its effects in the therapeutic relationship. I will begin by looking at the auditory sensory perception of sound and its role in the development of the infant, our perception of the world, the ‘self and others. I will then focus on the objective, physiological nature of sound in an attempt to answer some of the questions raised in my own mind about the possibility of this playing a vital role in our subjective experience of being with patients, with particular reference to the phenomenon of projective identification.