In her note Ann Peters makes a remarkable effort in bringing together data on fillers reported to occur in different languages. This is a difficult enterprise since these data have been obtained with different methodological tools and are anchored in different theoretical approaches. Peters tries to organize them under a loose but common underlying theoretical framework in which phonoprosodic, lexical, syntactic and morphological aspects of acquisition are considered as inherently interrelated and intertwined. Within this framework she is able to consider as related fillers that seem to stand for different kinds of language units (free and bound morphemes, but also amalgams and unidentifiable chunks that seem to stand for content words). She points out that fillers may be at the crossroad of these different kinds of traditional layers of language. As such, they may constitute traces of different kinds of work from the child's side and may have a role in changing the status of the child's knowledge in these domains.