Purpose: The aim of this research is to determine the reasons why Residential Aged Care Homes (RACHs) undertake the accreditation process, and to evaluate the influence that the accreditation system has on the quality of RACHs. Key literature/theoretical perspective: This research uses institutional theory to evaluate the influences of accreditation on RACHs, in terms of achieving legitimacy and/or improving levels of quality; it also determines the importance that RACHs assign to the standards of the accreditation process. Design/methodology/approach: This paper is exploratory in nature, using a descriptive research design with multiple case studies from New South Wales, Australia. Data collection using in-depth interviews and surveys is applied in this research. This will facilitate an examination of the data from two different perspectives: 1. from managerial staff directly involved with the accreditation process; 2. from other RACH staff. Findings: The pilot study for this research has been completed, resulting in amendments to the interview guides and survey instruments. Data collection is still in progress. Research limitations/implications: Theoretically this research has the potential to identify the reasons why RACHs adopt the accreditation standards and empirically, to address paucity in the current literature. Practical and social implications: This research has the potential to determine the influence that the adoption of accreditation standards has on the quality of aged care services and facilities provided by RACHs, how RACHs view accreditation, and to provide valuable insights and direction to the Australian Government regarding aged care policies. Originality: This research explores the relationship between accreditation and the importance that RACHs devote to the accreditation system from an institutional theory perspective.