This thesis examined the institutionalisation of ethics within Australian organisations. A particular focus is the role of the strategic apex, or executive level of the organisation, in establishing the environment in which an ethical culture can develop. The literature review examined both organisational theory and existing approaches to developing organisational ethical culture using formal mechanisms such as written policies, procedures, training and development and reinforcement strategies. This revealed the polarisation of ethics literature between compliance and integrity based approaches. This is seen to be consistent with only two forms of organizations, the mechanistic and organic structures. This was identified as a major flaw in ethics literature as it does not inform organisations about appropriate ethical design for organisations that fall in between this continuum. The review of organisational theory concluded that components of organisational structure are used to discuss organisational moral responsibility and are also the components of the compliance and integrity approaches to organisational ethics. A tentative hypothesis was established that organisational ethics systems would be more effective if they are in fit with an organisation's structure. The study utilised a qualitative case based research method, argued as appropriate given the focus being strategic alignment of organisational structure and ethics frameworks. Thus was also recognised as having limitations, specifically not addressing the behavioural impact of such strategies in a significant way. The study examined the ethical frameworks of three large organisations. This included: an analysis of background to the ethics strategy, the design process, who was given responsibility for design and implementation of the framework. The major characteristics of the program was considered, how it was encultured throughout the organisation and consideration of any evaluation mechanism. This was contrasted against the organization's structural characteristics to establish whether the ethical framework was in fit with the structure of the organization. The analysis and discussion identified that senior management support was evident in all three case studies and crucial to the development of an ethical culture. Extensive written policies (codes of ethics and conduct) were identified in all three cases; however, the extent of appropriate support systems determined the degree to which these policies were effective. There was a general lack of understanding of ethical systems within the organisation with little expertise evident by those responsible for the programs in terms of appropriate strategies for enculturation. Ineffective strategies were mainly due to lack of appropriate support mechanisms (communication, training, reinforcement and reward and review) or inconsistency between support mechanisms and other organisational policies A major conclusion of the thesis is that the strategies used for enculturation of ethics, are basic organisational design variables. As such ethical frameworks need to be informed by organisational theory so as to design systems that achieve fit which leads to greater effectiveness.