Prior research has primarily viewed external relations as sources of essential information, resources, and capabilities improving firm innovation and performance. For new ventures with limited in-house resources, such relations are even more important. This study compares two types of new ventures: academic spin-offs and non-academic start-ups, and how their network relationships affect the ventures' competitive performance. Results from a survey among new ventures started during 2003 in Sweden showed that academic spin-offs and non-academic start-ups were using different types of relations and resources to achieve competitive advantages which might be due to their origin. However, a common prerequisite among all the new ventures was that they all, to a large extent, needed expertise and advice to be competitive, and thus to perform better. Moreover, strong ties between a new venture and its partners contributed more to the venture's competitive performance than weak ties did, even within occasional relationships.