Oxindoles with adjacent tetrasubstituted stereocenters were obtained in high yields and stereoselectivities by organocatalyzed conjugate addition reactions of monothiomalonates (MTMs) to isatin‐derived N‐Cbz ketimines. The method requires only a low catalyst loading (2 mol %) and proceeds under mild reaction conditions. Both enantiomers are accessible in good yields and excellent stereoselectivities by using either Takemoto’s catalyst or a cinchona alkaloid derivative. The synthetic methodology allowed establishment of a straightforward route to derivatives of the gastrin/cholecystokinin‐B receptor antagonist AG‐041R. Crowd around: Oxindoles with adjacent fully substituted stereogenic centers were formed by mild organocatalytic addition reactions with high diastereo‐ and enantioselectivities. The synthetic versatility of the products with orthogonally addressable functional moieties was showcased in the synthesis of derivatives of the bioactive oxindole AG‐041R.