This article begins the work of examining what kind of doctoral experiences positively influence researcher development, and what other attributes may contribute to a successful research career. It reports preliminary findings from the analysis of survey responses by a sample of successful mid-career researchers. Positive doctoral experiences and the early establishment of research activity are found to be important to researcher development. Successful researchers were also found to be able to acknowledge the importance of their "soft skills", and to have flexible, responsive and adaptive dispositions. We term this disposition "an entrepreneurial subjectivity" and argue that it is an important and under-examined characteristic of the successful researcher.