Background: Infra-red and thermal imaging enable wireless systems to monitor patients’ vital signs and absence of wires may improve patient experiences. No studies have explored staff perceptions of this specific type of technology in the adult population. Understanding existing working systems before introducing technology could improve adoption. Methods: We conducted semi-structured interviews with Intensive Care Unit (ICU) staff exploring perceptions of wireless patient monitoring. We used the Systems Engineering Initiative for Patient Safety (SEIPS) model to guide thematic analysis. Results: We identified usability themes relating to staff perceptions of current patient monitoring experiences, staff perceptions of patient/relative expectations of ICU care, troubleshooting, hierarchy of monitoring, and consensus of trust. Conclusion: The concept of wireless monitoring has perceived benefits for patients and staff. The Systems Engineering Initiative for Patient Safety model guided a rigorous systems-based evaluation of the technology. The results highlight social and environmental factors which may influence usability, adoption, or abandonment of wireless technology in the ICU.