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Background and Aims Optimal patient positioning for popliteal sciatic nerve blocks remains a topic of debate. This study aimed to evaluate the clarity of nerve visualisation, ease of identification, and scanning efficiency across different patient positions using ultrasound.Methods In a randomised, crossover observational study conducted during a ‘Sonoclub’ ultrasound-guided regional anaesthesia course, 40 anaesthetists scanned volunteer models in four positions: prone, lateral, supine with knee flexed, and supine with knee extended. Outcomes included time to block-ready image acquisition, image quality (rated 0–3), and volunteer comfort (rated 1–3). The study was classified as quality improvement by the NIHR decision tool, this obviated the need for formal ethical approval.Results Participants had a mean of 12 years‘ anaesthetic experience and a median popliteal block confidence score of 4/5 (Using a Likert scale with 1 being not at all confident to 5 expert level). A one-way ANOVA to compare the effect of positioning on time to visualisation revealed there was a statistically significant difference between at least two groups (F(3,145)=3.417, p=0.019). While the majority (22/40) preferred the supine knee extended position in their clinical practice, the supine with knee flexed position yielded the fastest mean imaging time (32.5 seconds) and highest image quality (mean score 2.4). Despite the popularity in participants’ clinical practice, the supine with knee extended position was surprisingly associated with the longest time to visualisation (51.4 seconds).Conclusions Although the supine with knee extended position is commonly favoured, it may not offer the most efficient or clearest visualisation of the sciatic nerve. This position also often requires assistance with elevation of the leg and there are concerns regarding nerve stretch and consequent potential increase in likelihood of nerve injury. Supine with knee flexed in our study appeared superior and it may warrant broader adoption in clinical practice.