Two basic problems relating to solid/liquid waste are discussed in this chapter: first, how to control the solid and liquid wastes; second, how to recover and reuse these wastes as conventional construction materials if possible. All wastes discussed herein are urban refuse generally known as garbage, which covers five aspects: (1) basic characteristics of urban refuse (garbage) including composition, classification, and engineering behavior such as volume change, hydraulic conductivity, bearing capacity, and stress-strain-strength of compacted garbage; (2) decomposition processes of garbage in a landfill including causes, mechanisms, and settlement prediction; (3) compaction control during disposal process and the slope stability of the landfill in both newly established and abandoned landfill sites; (4) design and remedies of waste control facilities; and (5) utilization of waste for conventional construction materials.