Reliability building involves the techniques and procedures used to ensure a predetermined reliability level for a given product, as evaluated through reliability assessing. In this chapter, we describe the basic rules of reliability building. Then, we consider the failure risks associated with some representative types of discrete electronic components (capacitors, diodes, and transistors), identifying the possible failure mechanisms (FMs) (the physical-chemical processes that produce the failure) and recommending corrective actions. We conclude by examining electrostatic discharge (ESD), a FM that can arise in any electronic component, and we propose possible methods for preventing ESD.