We study the recurrence dynamics of queries in Web search by analysing a large real-world query log dataset. We find that query frequency is more useful in predicting collective query recurrence whereas query recency is more useful in predicting individual query recurrence. Our findings provide valuable insights for understanding and improving Web search. Categories and Subject Descriptors H.2.8 [Database Management]: Database Applications— data mining; H.3.3 [Information Storage and Retrieval]: Information Search and Retrieval General Terms Measurement Keywords Web Search, Web Mining, Query Log Analysis, Personalisation.