In emergent high technology industries, entrepreneurs and their new ventures play a critical role in enhancing economic growth. In these industries, we can easily see some new ventures grow more rapidly to outperform their competitors. However, looking beyond the surface, new ventures’ growth path is idiosyncratic. More specifically, when growing, new ventures pursue different paths in terms of 1) which technologies they develop, 2) which products they make, and 3) what markets they enter. The question that has struck me is why high-tech new ventures differ on these key strategic choices. Building on literature on entrepreneurship, strategy, industry evolution, and network, this dissertation tries to answer this important question by focusing on intra-firm factors, more specifically, the individual and structural attributes of new ventures. Types of founder experience and new ventures’ knowledge structure are examined in depth. My three studies, each presented as a separate essay herein, investigate how individual (i.e. founder experience) and structural attributes (i.e. knowledge structure) affect key strategic choices regarding i) product market scope (Wernerfelt and Montgomery, 1988), ii) technological search scope (Katila and Ahuja, 2002), and iii) the types of new products (Sanchez and Mahoney, 1996; Henderson and Clark, 1990), respectively. In each, I discuss the relevant theories, methodology, data sources, results and implications. By investigating intra-firm factors that trigger different entrepreneurial strategies, my dissertation responds to an important call – micro-foundation of strategy formation – thus filling a key gap in the entrepreneurship literature. / Business Administration/Strategic Management