Recalling an experience often impairs the later retention of related traces, a phenomenon known as retrieval-induced forgetting (RIF). Research has shown that episodic associations protect competing memories from RIF (Anderson & McCulloch, 1999). We report 4 experiments that examined whether semantic associations also protect against RIF. In all experiments, robust RIF occurred when there were few associations between practiced and nonpracticed sets, but RIF was abolished when there were many. The benefits of semantic integration were independent of episodic integration strategies and were not mediated by intentional use of the associations. Rather, these results establish a new boundary condition on RIF--semantic integration--that has a potent impact on the magnitude of RIF and may explain variability in the RIF phenomenon. (Contains 6 footnotes, 4 tables and 4 figures.)