The use of recorded environmental sounds in electroacoustic music has led to the raising of fundamental questions concerning the aesthetic criteria with which such materials should be approached in composition. One of the most fundamental issues has been the compositional role of "source recognition", whereby the listener assigns environmental sounds to their physical source objects or situations. This study deals with the potentials of source recognition in sonic art arising from the creative use of field-recordings, especially the potential for tangible "real-world” reference to be used as a criterion by which works are structured. Since recognition of sources is such an elemental aspect of the normal perception of sounds in the environment, this is regarded as a highly relevant basis from which to use field-recordings in composition. Particular emphasis is also given to the placement of this in the context of New Zealand work involving electroacoustic media, in an attempt to evaluate the compositional importance of New Zealand composers' concern for the environment in their works. Chapter one provides a background to the increased concentration in music of the twentieth century on the sounds and stimulus of environmental phenomena, and especially the use of natural sounds in electroacoustic music as it became possible with sound recording. Chapter two examines four approaches to the classification of natural sounds, which are based on different ways in which environmental sound can be perceived - from details of source recognition to focus on morphological and spectral characteristics. Chapter three examines in more detail the use of source recognition of environmental sounds in electroacoustic music by way of critique of two established approaches - namely, Simon Emmerson's writings on "mimesis" and Trevor Wishart's concept of "sonic landscapes", Chapter four explores the role of source recognition when working with field-recordings, both as a means of documenting the sounds of real objects and events, and as a structural force; particular emphasis is given to examples drawn from works by New Zealand composers. These four chapters together form part one of the study. The second part comprises interviews with eight New Zealand-born composers of electroacoustic music, as well as commentaries on the use of field-recordings in the work of these composers. Part three consists of analyses of selected New Zealand works in which field recordings have been used.