Why do some start-up firms raise funds from banks andothers from venture capitalists? To answer this question,I develop a model of start-up financing when intellectualproperty rights are not well protected. The upside of VCfinancing is that the VC understands the business betterthan a bank. The downside, however, is that the VC maysteal the idea and use it himself. The results of themodel are consistent with empirical regularities onstart-up financing. The model implies that thecharacteristics of the firms financing from venturecapitalists are low-collateral, high-growth and high-profitability. The model also suggests that thetighter protection of intellectual property rightscontributes to the recent dramatic growth of the USventure capital industry.