Aims: We used data from the General Longitudinal Overactive Bladder Evaluation (GLOBE) to understand predictors of variation in urgency and urinary incontinence (UI) symptoms over time. Methods: A random sample of Geisinger Clinic primary care patients (men and women) 40+ years of age were recruited for a survey of bladder control symptoms at baseline and 12 months later. Symptom questions used a 4-week recall period. Composite scores were derived for urgency and UI frequency. Logistic regression was used to evaluate predictors of variation in scores at cross-section and longitudinally. Results: A majority of those with UI symptoms and almost 40% of those with urgency symptoms reported episodes of once a week or less often; 17% had symptoms a few times a week or more often. Twenty-one percent with urgency symptoms and 25% with UI symptoms at baseline did not have active symptoms 12 months later. The strongest predictors of active symptoms at follow-up were baseline symptom score and duration of time since first onset of symptoms. Of those with no urgency symptoms at baseline, 22% had urgency at 12 months. Among those with no UI symptoms at baseline, 13% had UI symptoms 12 months later. Among the latter, age (males only) and BMI were the strongest predictors of symptoms at follow-up. Conclusions: Inter-individual and intra-individual occurrences of urgency and UI symptoms are highly variable in the general population. Use of established predictors to select individuals with less variability in symptoms may help to reduce placebo rates in clinical trials. Neurourol. Urodynam. 29:328-335, 2010. Copyright © 2009 Wiley-Liss, Inc.