Intensive care unit acquired weakness (ICUAW) is common in critically ill patients, contributing to substantial morbidity. Major trials and novel mechanistic findings published over the past years have advanced knowledge for the prevention and treatment of ICUAW. To streamline future research priorities, a multinational, interdisciplinary group of ICU clinicians, researchers, and people with lived experience convened to develop this evidence-based research agenda. Using a stepwise process including a systematic review with meta-analysis, two expert panel meetings, and a two-round modified Delphi method, we identified the top ten research priorities for ICUAW. Our report highlights the lack of reliable prognostic markers and mechanistic understanding that limit early diagnosis and treatment. Current evidence to treat ICUAW supports enhanced physical rehabilitation versus no rehabilitation, while higher dose enterally-delivered protein alone does not improve patient outcomes. However, the direct effects on muscles or appropriate dosing for patients with comorbidities remain largely unknown. The proposed ten key priority research questions integrate pathophysiology, diagnostics, treatment, and follow-up and emphasise personalised medicine and patient-centred outcomes over the continuum of recovery. Future research should focus on early prognostic markers, mechanisms of ICUAW, and identification of treatment responders allowing individualised dosing strategies tailored across the recovery trajectory. Defining meaningful outcomes, improving follow-up care, and integrating patient, family and caregiver priorities are essential. Advancing this agenda will require interdisciplinary collaboration and the use of emerging methods, including artificial intelligence, to support personalised and effective ICUAW care.