This article describes the design and implementation of MidiVisualiser, a virtual environment which provides an interactive visualisation of MIDI music data. Section 1 explores music visualisation in general and examines the role of computers and virtual environments. Section 2 briefly surveys existing music visualisation research and places MidiVisualiser in context. Section 3 examines various techniques of visualisation and discusses composite dimensions and ‘Benediktine cyberspace', including a description of how visualisation techniques derived from them were used in MidiVisualiser to overcome some of the difficulties associated with representing large numbers of data attributes simultaneously. Sections 4 and 5 contain an overview of the implementation and evaluation of MidiVisualiser, while section 6 discusses future work and conclusions.