The current study focuses on infants' sleep-wake states in group child care and relations of those states to infant-caregiver interactions. Qualitative case studies were conducted with four infants (3-7 months old) in an infant room at a child care centre. Video-recordings were the main format for data collection with the four infants and video recordings were made for a period of 3-5 h on each infant on a weekly basis for 11-12 weeks. Video recordings were transcribed using the InqScribe transcription software. Infant states identified in this research are important in the synchrony of infant-caregiver interactions, and have implications for caregivers' awareness of the impact of their actions associated with infant states. Caregivers took active roles in infant state modulation as it related to the infants' smooth or interrupted state transitions in the group care context. This research represents an effort to broaden and stimulate discussions on newer issues for enhancing infant child care practices and skills.