In this chapter, we will introduce the primary reliability challenges associated with IC packaging. These challenges encompass aspects such as thermal management, mechanical stress, electrical performance, substrate routing coupling, warpage, coefficient of thermal expansion (CTE), heterogeneous integration, and thinner substrates. These factors can lead to issues like warpage, fatigue, and cracks. Furthermore, we explore various inspection methodologies extensively employed as vulnerability detection methods, including wafer-level testing, 3D stack testing, thermal management techniques, etc. Additionally, potential solutions to these reliability challenges will be discussed, including the use of new materials, improved fabrication procedures, and innovative design techniques. By examining these solutions, we aim to provide insights into mitigating the reliability vulnerabilities introduced by IC packaging advancements.