The past three decades have seen a growing body of research into language learner metacognitive knowledge, strategy use, and the relationship between them. However, the correlation between knowledge about strategies and strategy use in ESL listening and speaking has not been explored. This study investigates 278 Singaporean students' knowledge and use of 40 listening and speaking strategies, and the relationship between these two variables. Distinctions were made among use-focused and form-focused learning strategies, comprehension strategies and communication strategies. The results showed that the students tended to believe in the usefulness of all four groups of strategies but seemed more often to use use-focused ones. Of the 40 strategies, 32 were perceived as useful by half the students, whereas only 13 were reported as used frequently. The discrepancy indicates that, while the students were generally aware of the usefulness of the strategies, they were not yet conscious and confident strategy users. There seems to be a need to increase their repertoire of strategies. Correlations were found between perceptions of the usefulness and perceived use of the strategies. The paper ends by considering teaching implications and future research.