A method for efficiently implementing a remembered set for a region-based garbage collector includes maintaining, for each region in an object heap, a remembered set card list (RSCL). Each card in the RSCL identifies an area in the object heap that includes at least one object that references an object in the region associated with the RSCL. The method further establishes a collection set identifying a subset of regions in the object heap on which to perform partial garbage collection. Prior to performing the partial garbage collection, the method flushes cards from RSCLs associated with the collection set to the card table, globally discards cards that are about to be rebuilt from all RSCLs, and globally cleans the card table. The method then adds cards to the RSCLs for inter-region references discovered while traversing live objects in the collection set. A corresponding computer program product and apparatus are also disclosed.