The results of Cognitive Intervention (CI) programs vary considerably; thus, it is helpful to assess the characteristics that enhance the effectiveness of these programs. Our objectives were to analyze the effectiveness of a multicomponent CI program called UMAM on cognitive performance, subjective memory, daily forgetfulness, and mood of individuals with memory complaints. Older adults with no cognitive impairment were separated into two groups by simple random assignment, a control (n = 111) and a parallel experimental (n = 115) group. They were assessed with an extended neuropsychological protocol and the Memory Failures of Everyday Questionnaire (MFE); evaluation pre and post intervention (at six months). We performed a multifactorial cognitive intervention (30 sessions) based on memory strategies, stimulation of cognitive processes, instruction in basic concepts about memory, interventions for everyday memory failures, and Metamemory. The Results showed improvements in objective measures, including logical memory (Cohen's d = 0.30); processing speed (d = 0.26); phonological (d = 0.33) and semantic verbal fluency (d = 0.27); and general cognitive performance (d = 0.82) (all, p < 0.05). In subjective measures, we found improvements in mood state (d = 0.25) and everyday memory failures (MFE: d = 0.29) (all, p < 0.05). Several everyday failures improve: 'Forgetting where you have put something,' "finding a word that is on the 'tip of the tongue,' and 'checking again if something has been done' (all, p < 0.05). We found positive results when a cognitive process was directly trained intensely using exercises that focus on real life, with adaptive activities that aim to resolve everyday memory failures. This program has proved effective in promoting health and well-being and preventing cognitive impairment.