This paper reports in-depth case study material which illuminates the impact of early aiding on the rate of acquisition of communicative and linguistic behaviours of a small group of severely and profoundly deaf infants (average better ear impairment of 101 dB) aided between 3 and 6 months of age. A comparison is made of each infant's development of gestural and vocal productions between the ages of 6 and 21 months. Data derive from video- and audio-recorded social interaction between deaf and hearing infants and their principal caregivers taken across three contexts. The effects of earlier identification, amplification and fluctuations in early auditory stimulation, on the deaf infants' acquisition of communicative, symbolic and linguistic skills are discussed.