In this account, we summarized our recent efforts to develop molecular transformations under Brønsted base catalysis on the basis of our own guiding principles for designing reaction systems, that include “the generation and application of anionic species which are difficult to utilize in conventional reaction systems” and “the employment of organosuperbases possessing much higher basicities than conventional organic bases as a catalyst”. In particular, we discussed reactions involving the generation of carbanions of less acidic compounds through the formal umpolung process from carbonyl compounds and formal [3+2] cycloadditions involving the generation of the synthetic equivalent of a 1,3-dipole through epoxide opening.