“Continuous” monitoring of specific biomarkers in real-time offers longitudinal information that can enable not only rapid medical decision-making but also early disease detection. As opposed to the current end-point diagnostics approaches, such a continuous-monitoring capability introduces a new dimension in achieving precision medicine and precision health. In this talk, I will present my research contributions toward this goal. Specifically, my research harvests the power of CMOS integrated circuits, applied physics, and advanced biotechnology to address biosensing requirements on sensitivity, specificity, throughput, multiplexing, device miniaturization, and system scaling. I will focus on two developed technology platforms: (1) an electrochemical-sensing wireless implant for in vivo monitoring of small molecules using reagentless structure-switching “aptamers” and (2) a cytometry-on-CMOS platform for high-throughput studies of the electromagnetic signatures at GHz frequencies. The former has broad applications including precision drug dosing and early disease detection whereas the later has the potentials for sensing circulating-tumor-cells in blood. I will address their critical needs as well as circuits and systems design challenges. I will also present my recent activity in developing high-resolution intraoperative imaging tools, circuit techniques to overcome density constraints in neural-recording probes, sensing platform for “distributed” diagnosis, and low-power heart-rate-sensing wearables.