The purpose of this thesis is to examine and extend Robert Stebbins's (1992) concept of serious leisure by explicating the improvisatory nature of jazz and arguing that Stebbins's concept of play does not allow for pursuits, such as jazz, to be considered serious leisure. The research engages a philosophical enquiry as defined by Bergmann Drewe (1996): Philosophical enquiry involves reviewing the relevant literature and putting forward positions which agree, oppose or extend the arguments presented in the literature. Reviewing the relevant literature and putting forth alternative arguments or extending the arguments will involve the following strategies and activities: (a) identifying philosophical positions and clarifying the concepts involved, (b) illuminating the assumptions underlying particular positions, (c) explicating the justification for particular positions, and (d) examining the implications of philosophical arguments for practitioners in the area of leisure. vskip18pt I have reviewed the relevant literature in the areas of leisure, serious and casual leisure, play and jazz. In chapter one, I examine leisure, and contrast the concept of casual leisure with serious leisure. Chapter two explores and illuminates various p ay concepts. In chapter three I explicate and compare jazz, with its inherently fundamental play features, with the components of serious leisure, arguing that jazz is a form of serious leisure. Finally, in chapter four, I juxtapose play and jazz and conclude by recapitulating the need to extend Stebbins's model of serious leisure to include play.