The aim of this study is to examine how caretakers speak to young children in a day-care centre and particularly to investigate how they adjust their language, according to children's age and to size of groups. Five Italian teachers were observed, each one during six different sessions. Children's ages were o; 10-1 ;2 and 256-3;o. The number of children varied from a rather large group (seven children) to a small group (three children) to a single child. Language was taperecorded during free-play sessions of ten minutes. Context was noted by two observers. Transcripts were analysed according to structural features (syntactical complexity, redundancy, type-token ratio, speed) and functional features (proportion of utterances with different purpose: control and organization of child behaviour, empathy, conversation and teaching). Results show some significant differences in structure and function according to children's age and group size.