This study investigates the seismic and structural performance of a G+10 reinforced concrete (RC) building with and without shear walls. Using STAAD.Pro and adhering to IS 456:2000 and IS 1893:2016, two structural models were analyzed: a bare frame and a frame with strategically placed shear walls. Key performance parameters such as lateral displacement, storey drift, base shear, and time period were compared. Results show that incorporating shear walls reduces top-storey displacement by nearly 50% and inter-storey drift by over 55%, while increasing base shear due to higher stiffness. The natural time period decreased significantly, indicating improved dynamic response. The study confirms that shear walls enhance seismic resilience, reduce design demands on frame elements, and support safer, more economical construction in mid-rise buildings.