Cancer is among the leading causes of death worldwide. Cancers generate their own network of blood vessels to provide nutrients and oxygen to grow and spread. Detecting these developments early and treating them increases the chances of survival. However, current imaging methods are unable to detect these microscopic structures deep within the body. Therefore there is a crucial need to develop new imaging techniques that can fill this requirement. Additionally, imaging techniques which can look at the full 3D region of disease are urgently needed to reliably assess these. The research in this proposal is designed to develop and demonstrate an ultrasound imaging technique known as ultrasound super-resolution (US-SR) in 2D and 3D in the clinic. US-SR is able to image extremely fine details of the blood vessel network, previously unseen with standard ultrasound imaging. This technique involves adding small amounts of microbubbles into the blood stream, which show up on the ultrasound images because the sound is more strongly reflected from the bubbles than other tissues. These bubbles circulate harmlessly within the vessels until they dissolve after a few minutes. By pinpointing the location of these travelling bubbles over time, we can build up an image which 'paints out' the vessel structures containing those microbubbles. The ability to see these small vessels using ultrasound, which is able to image at depth (>10 cm) in humans, has the potential to identify these important changes in the vascular network Currently, however, US-SR has only been demonstrated in a small number of patients, it requires long scan times (in the range of 10s of minutes depending on the target) and ultrasound use in hospitals is generally limited to 2D. Within this proposed fellowship, it is my aim to firstly, develop faster ways to acquire the data needed to create these images. Secondly, to demonstrate the use of 2D US-SR in a large number of patients. And lastly, to use these developments to move 3D US-SR into the clinic. Successful 3D clinical US-SR demonstration could propel this technique into clinical practice. Its use could provide safe, low-cost microscopic assessment of blood vessels associated with disease. This could be crucial to patients with a wide range of micro-vascular related diseases including cancer due to early diagnosis and treatment. Given that US is an affordable imaging technique compared to for example x-ray CT and MRI, this could also provide significant cost-savings for the NHS.