We analyze the funding of start-up companies across financing rounds, focusing on the dynamic interactions between angel investors and venture capitalists. Using unique data from British Columbia, Canada, we show that angels and venture capitalists are dynamic substitutes. This substitutes pattern applies across the performance range of companies. It is less pronounced for serial angels. An instrumental variable analysis, based on available investor tax credits, suggests that the substitutes pattern is driven by company characteristics. Overall, the evidence points to the existence of parallel streams of angel and venture capital funding, with fewer transitions between streams than is traditionally assumed.