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Delivering precise image-guided radiotherapy is challenging for cancers in upper abdomen, including the liver, pancreas and other oligometastases, due to breathing motion and highly deformable soft tissue anatomy that is not well visualized on standard cone-beam CT (CBCT) imaging. Breathing motion amplitude must be managed to avoid overly-large planning margins that impact normal tissue doses and inhibit dose-escalation. Voluntary and device-assisted imaging and treatment delivery in breath-hold can suspend motion at a given respiratory phase (e.g. inhale or exhale) though is not suitable for all patients such as those with language barriers and poorer performance status. Even with excellent patient compliance, some patients have of non-reproducible breath hold positions (breath-to-breath, and intra-breath hold drifts). Alternatively, abdominal compression devices can reduce breathing amplitude in some patients though they are very uncomfortable for many. There is a risk of compression devices impacting normal tissue deformation in the abdomen which may prevent dose-escalation (e.g. compression the duodenum near pancreas targets). Possible contraindications exist limiting the use of these devices (e.g. colostomies and ascites for compression, etc) so many patients may ultimately have radiation under free-breathing. Given this variability, patient-specific evaluation of motion management under imaging can allow for optimal, personalised strategies to be used. Breathing motion can be characterized with imaging with a high temporal resolution ranging from simple 2D kV fluoro of the diaphragm, to cine-MR for direct tumor visualization, and 4D CT, CBCT or MR imaging to fully model organ motion and targets in multiple planes. Assessment of breathing motion should occur upfront at planning and daily during IGRT as inter-fraction changes in breathing patterns have been observed. IGRT in the upper abdomen is -particularly challenging with CBCT given the lack of soft tissue contrast and highly deformable organ including the liver, pancreas and luminal gastrointestinal organs that are additional subject to filling and emptying. Consistent dietary preparation can mitigate some of the largest inter-fraction changes however this is ineffective for many patients. In the absence of implanted markers that are visible on CBCT, IGRT largely relies on soft-tissue targeting as baseline shifts in position relative to bony anatomy in excess of several centimeters are common. Other surrogate landmarks can be used to target tumors, including normal tissue boundaries. Oral contrast can be administered prior to IGRT when stomach and duodenum are at-risk and required careful avoidance during CBCT-guided treatment. Deforming tissues, including when multiple tumors are simultaneously targeted, can be partially accounted for with focused image registration and corrections with tilt-and-roll tables. In a minority of patients, deformation necessitates adaptive re-planning, either offline following repeat CT simulation or online with some CBCT and MR-enabled linacs. Successfully clinical application of these strategies allows for high-quality IGRT and safe application of dose-escalation and normal-tissue sparing radiotherapy to deliver optimal outcomes for patients with upper abdomen tumors.