Public information that becomes available after a manager's initial voluntary disclosure decision creates incentives for her to reconsider and possibly change that decision. We show that if she has private information that is value relevant or that impacts the firms ability to compete in its product market, the option to revise an initial disclosure decision in the face of a public release of information alters both the initial decision and the overall frequency of disclosure. These effects are amplified if she believes that public information arrival is more likely or if the firms value is more sensitive to it. We also show that an increase in the initial disclosure cost reduces the probability of an initial disclosure and increases the probability of a subsequent disclosure. These effects are reversed if the cost of a subsequent disclosure increases.