Publisher Summary A product more often than not is the assemblage of various individual components. The spatial alignment between functionally important components is what makes the product function. This chapter emphasizes the importance of designing for ease of assembly and disassembly. Assembly of a product is a function of design parameters that are both intensive (material properties) and extensive (physical attributes) in nature. Its design parameters include shape, size, material compatibility, flexibility, and thermal conductivity. When individual components are manufactured with ease of assembly in mind, the result is a significant reduction in assembly lead times and savings in resources (both material and human). It is imperative that each component be designed in such as way as to align efficiently. This entails the design and processing of the component in a specific manner with respect to shape, size, tolerances, and surface finish. On the other hand, disassembly is the organized process of taking apart a systematically assembled product to enable maintenance, enhance serviceability, and/or to affect end of life objectives, such as product reuse, remanufacture, and recycling. It is not necessarily the opposite of assembly. Components need to be designed for disassembly so that the process can be effected without damage to the parts’ intensive and extensive properties. Its importance can be attributed to growing scarcity of natural resources, increased processing costs for virgin materials (such as mining iron ore for steel manufacturing), and environmental legislation to make manufacturers more responsible with regard to waste disposal.