High-quality imaging of the human body either at rest or when performing specific tasks is an important tool in diagnosing pathological changes in tissue structure and function. The ability to use two or more imaging systems simultaneously (multimodality imaging) significantly increases the power of diagnosis. Some of the most advanced European technical and medical institutions have come together on the EU-funded project 'Three modality contrast imaging using multi-functionalised microballoons' (3MICRON) to push medical imaging beyond the current state of the art. Microballoons (MBs) are novel micro/nanodevices that can be used as contrast agents. In the future, they could also be used for minimally invasive drug delivery. 3MICRON is developing and testing MBs for effectiveness as contrast agents as well as for bioclearance and biotoxicity. Selected MBs will then undergo pre-clinical testing. Scientists are focusing on their use in multimodal ultrasound (US), magnetic resonance imaging (MRI) and nuclear medicine applications such as single-photon emission computed tomography (SPECT). Such a combination will enable powerful three-dimensional (3D) functional imaging of cells, tissues and organs. Partners are currently developing three different types of polymeric MBs. Several functionalised MBs have demonstrated promising potential as ultrasound (US) contrast agents. In addition, a number of MBs were modified and tested for the optimisation of properties regarding use as MRI contrast agents and the potential for up-scaling production. Partners have built test setups simulating blood vessels to evaluate the multimodal imaging capabilities of the new contrast agents and optimisations are currently underway. Studies of biocompatibility are assessing the formation of a protein corona around the MBs – the body's response to foreign substances that determines their biological fate. Preliminary in vivo multimodality imaging of the carotid arteries in animal models is also currently in progress with development of relevant imaging software and protocols. 3MICRON is developing the technology for the use of MBs as contrast agents for multimodality imaging. State-of-the-art non-invasive and early diagnosis of debilitating and life threatening diseases will a have major impact on health care costs and patient quality of life.