The nonreductionist assemblage ontology/analytic is introduced to conceptualize tourism destinations as “multiplicities defined by assemblages” to more satisfactorily theorize and analyze their complex socioecological nature, unpredictable dynamics and motley identity, and guide planning or management decisions. Alternative conceptions of destinations—container, unitary whole, and relational place—are critically reviewed. The main tenets of Assemblage Thinking are presented and guide the ensuing analysis of destinations. The contribution of the assemblage ontology/analytic to destination studies and future research are summarized. The proposed conception calls for synthesizing complex systems and relational theoretical frameworks, employing methodological pluralism, and pursuing adaptive governance to foster the emergence of fittingly cofunctioning tourism and nontourism assemblages at destinations.