Modified Project Summary Section Bioelectronic implants provide a versatile platform for diagnosis, therapeutics as well as basic research but require invasive surgery. Here, we propose a paradigm shift: the ‘Circulatronics’ technology, wherein ultra-small bioelectronic devices target desired regions in the body for sensing and treatment, without the need for surgery. Its realization requires: i> nanoelectronic devices that are aggressively miniaturized (to fit inside vasculature) and extremely low power (to work deep inside body with low harvested energy); ii> heterogeneous integration of power-source and nanoelectronic circuits in a single device platform; iii> targeting the diseased regions for implantation without surgery. Accomplishing these requires innovations in diverse fields of applied physics, nanoelectronics and bioengineering and we are uniquely enabled due to our expertise in not only physics and solid-state nanoelectronic devices but also in bioelectronics, synthetic biology and neural engineering. We will build upon our work in developing ultra-scalable and record-low power nanoelectronics, which can lead to beyond-Silicon dimensional scalability to achieve i) and create sub-cellular sized and highly energy-efficient nanoelectronic devices. Moreover, we will leverage our research in building novel van der Waals heterostructures employing heterogeneous material systems enabled by atomically thin 2D materials to accomplish ii). For achieving iii), we will explore different surface functionalization techniques and leverage our expertise in synthetic biology. Circulatronics is a radical technology which can change the landscape of the field of biomedical implants and transform bioelectronic medicine. By alleviating surgery, it not only offers ultra-low invasiveness but can extend healthcare to patients not suited for surgery. These devices can modulate biological signals and can also integrate sensing functionalities. Since they can reach every nook and cranny of the body, they can obtain information from and treat intricate regions in body, which cannot be accessed by other technologies. Moreover, being extremely small, they can interact at a single cell or even subcellular level, to provide highly precise diagnosis and therapeutics as well as fundamental insights into biology.