The recognition by societies of the problems caused by deafness and hearing impairment has led to a significant increase in the need for audiologists. Additionally, the rapid development of audiology in the last few decades, a wide diversity of audiology education programs, and increased globalisation highlighted the need to evaluate current audiology education and practice from an international perspective. A major aim of this thesis was therefore to study comparative audiology, to allow systematic analysis of what hearing health care is needed worldwide, and the strategies required to achieve future improvements. Rather than remaining theoretical, this thesis also aimed to develop an affordable and sustainable seeding model for audiology education, which would build capacity in countries with inadequate audiology education. An international study surveyed major audiology organisations, and completed surveys were received from 62 countries (representing 78% of the world population). Eighty-six percent of countries needed more audiologists, and cited a lack of government funding, low public awareness of deafness and inadequate audiology education as major reasons for the shortages. There was a wide range of professionals providing hearing health care and a large overlap in their scope of practices. To discuss these complex issues, a conceptual model for hearing health care was developed which formalised the interacting issues, and highlighted the feedback loops between them. The conceptual model presented a framework that was used to discuss individual countries in more detail, and provided a basis for the design of strategies aimed at improving hearing health care and education for groups of countries. Although five distinct groups were described, in practice, most countries may benefit to some extent from hearing health care systems that range from decentralised community-based models (providing basic care), to more institutionally-based models (offering advanced services and technologies). Evolution of hearing health care systems from basic community-based, to more advanced institutionally-based services, would presumably come with strengthening economies and health and education infrastructures, and concurrent growth in audiology education and private and public hearing health care markets. The rate at which this occurs depends in part on the strength of a country’s economy, but also on its other health priorities, the equality of its wealth distribution, the diversity and geographic spread of its population, and the adequacy and efficiency of its hearing health care education programs.