the distinction between the novice, serial and portfolio entrepreneurs is an example of behavior-based categorization. other examples are the (related) studies by, on start-up event sequences. nascent entrepreneurship that emphasizes the series of activities involved in new venture emergence, rather than the solitary act of exploiting an opportunity. such research will help separate entrepreneurial action into its basic sub-activities and elucidate the inter- relationships between activities, between an activity (or sequence of activities) and an individual's motivation to form an opportunity belief, and between an activity (or sequence of activities) and the knowledge needed to form an opportunity belief. with this research, scholars will be able to begin constructing a theory of the micro-foundations of entrepreneurial action.