This chapter introduces metal–organic framework (MOF) and reticular chemistry, and contrasts MOFs to traditional carbons and zeolites. A brief discussion of how computational chemistry enables MOF design is presented, followed by a discussion of the types of problems that researchers think can be solved using MOFs. Current challenges in the MOF field are discussed. In particular, the vast number of MOFs can make selecting a MOF for a particular application difficult, the current small-scale production of MOFs results in some MOFs that are more expensive than traditional materials, and given the large number of MOF materials, not all of the MOFs reported in the literature are chemically stable in all applied environments. Lastly, the purpose and structure of the text is discussed.