The study investigated the relationship between cognitive factors and gains in number recall following training in a number-consonant mnemonic in a sample of 112 older adults (M = 70.9 years). The cognitive factors examined included baseline episodic memory, working memory, processing speed, and verbal knowledge. In addition, predictors of maintenance of gains to a follow-up assessment, eight months later, were examined. Whereas working memory was a prominent predictor of baseline recall, the magnitude of gains in recall from pre- to post-test assessments were predicted by baseline episodic memory, processing speed, and verbal knowledge. Verbal knowledge was the only significant predictor of maintenance. Collectively, the results indicate the need to consider multiple factors to account for individual differences in memory plasticity. The potential contribution of additional factors to individual differences in memory plasticity is discussed.