Disclosure by firms would seem to reduce the informational asymmetry that causes investment inefficiency in firms. However, the effect of disclosure is subtle, especially when the link between dis-closure and firm value is endogenous and depends on incentives within the firm. We analyze various disclosure regimes and determine which ones are effective in a model with optimal renegotiation-proof contracts. It is not effective to disclose only accepted contracts, but it is effective to have additional disclosure of all contract negotiations or, more reasonably, to allow forward-looking an-nouncements. The model is robust to renegotiation in equilibrium and is also robust to changing who offers any renegotiation. The analysis illuminates optim...