Quasi-zero stiffness (QZS) systems are critical for vibration isolation, combining high static load capacity with low dynamic stiffness to enable effective low-frequency vibration damping. This article reviews QZS principles, applications, and advancements, emphasizing their role in aerospace, semiconductor manufacturing, medical imaging, and robotics. QZS achieves near-zero effective stiffness by balancing positive stiffness elements (springs, beams) with negative stiffness mechanisms (magnetic repulsion, buckled beams), ensuring robust vibration isolation across operational ranges. A novel compact 3D design is introduced, employing elastic torsional deformation and spatial guides to transfer motion nonlinearly. This configuration minimizes static displacement, maintains a near-constant restoring force, and optimizes space efficiency for constrained environments. Beyond mechanical innovations, the article highlights progress in active control, metamaterials, and energy harvesting, which enhance system tunability and sustainability. However, challenges persist, including nonlinear dynamic complexities, precise parameter calibration, and material limitations. Future research should focus on experimental validation of theoretical models, machine learning-driven optimization, and smart materials (e.g., 4D-printed structures) to expand QZS adaptability. Integrating theoretical insights with engineering solutions could elevate QZS systems’ reliability, efficiency, and precision, advancing their industrial applicability. By addressing current limitations and leveraging emerging technologies, QZS frameworks hold promise for transforming vibration-sensitive sectors through enhanced stability and performance.