New Technology-based firms - from conceptualization to application

New Technology Based Firms (NTBFs) have gained increasing economic relevance, supported by the recognition that they play an important role in national economies in the appearance of both new, high technology products and of new and emerging industries. Despite their economic importance, a number of alternative definitions of NTBFs are referred in the literature, many of them adjusted to the aim of the study or the sample under observation. Such lack of conceptualization led to the need of a coherent framework for the study of NTBFs. No agreement exists so far on which are the key characteristics of NTBF. This lack of consensus in the conceptualization does not permit an adequate applicability of the concept or a comparison throughout the different existing studies. This is the motivation and the challenge underlying the dissertation. Firstly, we review and systematize the existing definitions and this endeavor aims to sustain a new and/or a revised definition. Then, we apply the proposed definition to a set of small, high tech firms, the so called ¿academic spin offs¿ incubated in the U. Porto, trying to assess the extent to which this group of firms might be classified as NTBF's.