We consider a real option model in which a cash-constrained entrepreneur learns prior to investing, but at a speed which is private information. The entrepreneur seeks outside funding, and uses the timing of his investment to signal his condence in the venture, and accordingly obtain cheaper credit. In the benchmark case with no informational friction, we show that the optimal investment date may be nonmonotonic or decreasing in learning speed, depending on the prior NPV of the project: better learning increases the value of the option, but also increases the speed of updating. In the presence of asymmetric information, the cash constraint may result in distortions in the investment timing policy, and the ine ciency is higher the more stringent the constraint. In addition, the welfare loss is sometimes higher for projects of higher quality. Ine cient investment policy may take both the form of over-investment (hurried investment as compared to the benchmark), when both entrepreneur types learn su ciently fast, and of under-investment (delayed investment), when the slow-learning type does not learn fast enough. Therefore, the severity of the cash constraint a ects the magnitude of the timing distortion, but not its direction.