Development of highly efficient catalytic processes for the synthesis of natural and unnatural compounds of medicinal interest or useful as intermediates for functional materials is a central focus in modern organic synthesis. One of the most efficient approaches to such methodology developments is to apply transition-metal catalyzed cyclization reactions for the transformations of simple starting materials into monocyclic, bicyclic, and polycyclic scaffolds that can be further elaborated into specific targets. This article concisely summarizes recent advances in the cyclizations promoted by homogeneous catalysts, including various carbocyclizations, carbonylative carbocyclizations, cyclohydrocarbonylations, intramolecular hydrosilylations, and silylformations, compiling relevant references up to late 2008. Among these catalytic cyclization processes, the carbocyclization and carbonylative carbocyclization are extremely important and useful reactions for the syntheses of a variety of carbocyclic and heterocyclic compounds. Cascade carbocyclization is a powerful method, providing a rapid access to polycyclic skeletons in one step. Cyclohydrocarbonylation is another powerful catalytic cyclization process, which finds a host of applications in organic syntheses. Intramolecular hydrosilylations and silylformations also provide unique methods for a variety of organic syntheses. Accordingly, catalytic cyclization reactions not only serve as highly useful synthetic methods in laboratories but also have high potential as future industrial processes.