Musical criticism lies at the heart of music education. It is argued that there are five fundamental dimensions of musical criticism: control of sonorities; expressive characterisation; structural relationships; personal evaluation; historical and technical context. The first four of these – those directly concerned with response to a musical object or event – are the essential modes of criticism and these can be seen unfolding in the musical development of children. Following the publication in 1986 by Swanwick and Tillman of a musical development model, further research in Cyprus gives supportive results; showing strong agreement between judges on the use of critical criteria for assessing children's compositions and articulating the same sequential order of development. A random selection of children's compositions drawn from over 600 items collected in Cyprus is assessed by independent judges. There are correlations between assigned critical criteria and the age of the children. Thus the pattern of musical development can be seen to parallel a critical hierarchy. From these data we can also assume that, although the sequential order of development may be confirmed, the compositions of the UK children in our sample appear generally to be more advanced than those of their Cyprus peers. The quality and consistency of music education provision seems therefore to have a positive role in the development of critical powers. There are implications for music curriculum development, for assessment procedures and for further work on musical development, and on the relationship of composing to performing and of both to audience listening.