Background/Aim: Patients are admitted to an intensive care unit (ICU) for critical care not available to patients in the general wards, with the potential for reversible organ failure as a key admission criterion. The objective of this integrative review was to examine and discuss the literature pertaining to the environment of the ICU, including unit organisation, staffing and equipment, that underpins the provision of ICU services. This review also aimed to discuss current perspectives on ICU resources and utilisation. Methods: To prepare this integrated literature review, computer-assisted searches were conducted using the PubMed/Medline, CINAHL and EMBASE databases. An extensive search of library databases was undertaken using relevant keywords and related article searches. Studies were included if they were rated by a single investigator to have relevant content in these areas. Due to the breadth of the review, a structured approach was taken to integrate the relevant findings. Results: There was limited literature examining the relationships between these important areas. There was some evidence that a closed model of ICU care is associated with improved outcomes and less resource utilisation compared with an open model of ICU, although there was conflicting evidence for critical care delivered outside of the ICU. Critical care may be most effectively provided via a team model. The heterogeneity of the ICU setting, in particular the unique aspects of the delivery of ICU care in the Australasian model, hampered the ability to draw broad and clinically meaningful conclusions. Conclusions: Due to the increased demand for ICU services, ongoing evaluation of the long-term outcomes of ICU on the efficient use of resources to optimise patient outcomes is imperative. Results from the current evidence base suggest that rather than broad-based adjunctive services, refinement and subsequent evaluation of intensive care services in targeted and specific populations may be required, and that empirical evidence for the support of many organisational, structural, equipment and staffing aspects of ICU service delivery is lacking. Further research is needed to investigate the relationships between existing and conceptual models of care and direct patient outcomes.