Syntheses and applications of interlocked polymers, polyrotaxanes, and polyca-tenanes, including corresponding oligomers are reviewed with emphasis on (i) synthesis of interlocked polymers consisting of interlocked structures as the monomer-linking units (genuine "topological" polymers), and (ii) application of the interlocked polymers in both bulk and molecular levels. Further, the review also refers to a few important polyrotaxanes and polycatenane which are still unknown despite many synthetic challenges attempted so far. The review mainly summarizes the recent progress in the chemistry of polyrotaxanes and polycatenanes during this decade, in terms of kind of ring systems.