Objectives: To investigate processes for delivering early mobility interventions in adult intensive care unit patients used in research and quality improvement studies and the role of nurses in early mobility interventions. Methods: A systematic review was conducted. Electronic databases PubMED, CINAHL, PEDro, and Cochrane were searched for studies published from 2000 to June 2017 that implemented an early mobility intervention in adult intensive care units. Included studies involved progression to ambulation as a component of the intervention, included the role of the nurse in preparing for or delivering the intervention, and reported at least one patient or organisational outcome measure. The System Engineering Initiative for Patient Safety (SEIPS) model, a framework for understanding structure, processes, and healthcare outcomes, was used to evaluate studies. Results: 25 studies were included in the final review. Studies consisted of randomised control trials, prospective, retrospective, or mixed designs. A range of processes to support the delivery of early mobility were found. These processes include forming interdisciplinary teams, increasing mobility staff, mobility protocols, interdisciplinary education, champions, communication, and feedback. Conclusion: Variation exists in the process of delivering early mobility in the intensive care unit. In particular, further rigorous studies are needed to better understand the role of nurses in implementing early mobility to maintain a patient's functional status. (C) 2018 Elsevier Ltd. All rights reserved.