The Australian aquatic theme park segment is a vibrant and significant part of the Australian tourism industry because as a tourism generator it is a direct contributor to the economy and to employment growth. Research in this area can provide a deeper understanding of the complexities of the industry and its future effectiveness. Tourism organisations, such as aquatic theme parks, need to rely on the commitment and performance of a well-trained, multi-skilled workforce in order to achieve a competitive position, especially in terms of providing high quality customer service. This suggests that tourism organisations need to adopt effective organisational practices that enhance the motivation of employees and improve organisational effectiveness by providing the level of quality customer service required to become and remains competitive. Although the tourism industry in general and the theme park segment in particular make an important contribution to the Australia economy, minimal research has been undertaken to determine the factors that contribute to the effectiveness of organisational practices that influence work-related outcomes (commitment, job satisfaction and employee performance). As a related issue, no research has been undertaken to examine the perception of professionalism of employees undertaking marine science activities within Australian aquatic theme parks. Accordingly, one of the objectives of the present research was to examine the impact of organisational practices (training and communication) on affective commitment, job satisfaction and employee performance within the Australian aquatic theme park segment. The second objective was to examine whether the impact of such organisational practices on these work-related outcomes varies between employees designated to undertake marine science related activities and other theme park employees (salespersons, food and beverage and administrative). The final objective of this research was to examine whether employees designated to undertake marine science related activities perceive themselves as professionals. The Meaning of Working Theoretical Framework (based on the Meaning of Working (MOW) model developed by Westwood and Lok, 2003) is used in this research as a conceptual framework to enable a better understanding of the meanings and significance that aquatic theme park employees attach to their work roles. Understanding the basic meanings that individuals attach to their work roles provides relevant insights into the nature of employee commitment, job satisfaction and employee performance, given the apparent impact of perceived work significance on employee attitudes and behaviours. Application of the Meaning of Working Theoretical Framework therefore broadened the conceptual framework of the present research to include and clarify the central constructs of commitment, job satisfaction and employee performance in Australian aquatic theme park workplaces. The present study was undertaken with employees from three Australian aquatic theme park companies, including 'marine science employees' and 'other theme park employees', with a particular emphasis on the former group of employees. The nature of the current study suggested the value of using both quantitative and qualitative methods (mixed methods methodology) and so, the adoption of the pragmatist paradigm was appropriate in framing and answering the thesis’ research questions. Quantitative and qualitative methods in this study were conceptualized, designed and implemented sequentially. Quantitative methods (e.g. survey) were conducted first in order to develop a level of generalisation that not only added knowledge to the theory but also enabled a prediction in understanding levels of commitment, job satisfaction and employee performance. Qualitative methods (indepth interviews and focus group discussions) then provided in-depth information and insights into the link between organisational practices (e.g. training and communication) and work-related outcomes and perceptions of professionalism for marine science employees. The findings of this study have broadened the scope of the MOW model developed by Westwood and Lok (2003) in a number of significant and original ways. In particular, consideration of the relationship between employees and customers and analysis of the values maintained by the organisational culture and their influence on the particular subcultures within the organisations studied proved to be essential in understanding the work meanings patterns in this study. The present study further developed the MOW model by clearly demonstrating the critical role played by training and communication in influencing patterns of work meanings. In addition, this study also expanded the Westwood and Lok’s (2003) MOW model by including issues related to professionalism. The findings of the present study highlighted the pivotal role played by a key HRM practice (on-the-job training), which is more relevant in influencing work-related outcomes than the impact of communication processes, as demonstrated in the study data and analysis. Contrary to expectations, the findings suggested that communication processes play an indirect role in influencing organisational effectiveness, in terms of providing high quality service because of an identified ‘gap’ in beliefs and behaviours regarding customer service. Both training and communication processes appeared to be relatively ineffective in reducing this ambiguity regarding customer service for both group of employees within the aquatic theme parks studied. This should lead to a re-thinking of both training and communication practices to enhance the focus on, and delivery of quality customer service. A number of suggestions are canvassed. Another major finding of this thesis indicates that marine science employees not only perceive themselves as professionals but their status (job/occupation) within the tourism community supports a perception of emerging professionalism. The results revealed in the present study have the potential to impact positively on the tourism industry in general and on the aquatic theme park segment in particular. However, it is clear from the present research that the vibrancy of the tourism industry and the aquatic theme park segment can only be enhanced with more attention to communication and training, with an emphasis on improving employee self-efficacy, especially in the area of customer service.