Extant literature has typically drawn from the behavioral theory of the firm (BTOF) to examine new product introductions in the context of well-established companies. This paper extends the behavioral theory of the firm to entrepreneurial firms and argues that jointly considering founders' dispositional optimism together with the performance feedback promises to yield a better understanding of new product introductions in new ventures. We analyze a longitudinal dataset on the activities of 344 newly founded high technology ventures in the United States. The key insight of our study is that when BTOF is applied to the context of nascent, entrepreneurial ventures, the personality and dispositional characteristics of the entrepreneur must be considered. Specifically, we find that performance attainment discrepancy leads to new product introductions, but only when the entrepreneur's dispositional optimism level is high.