This paper marks a milestone in a six year research cycle on weak signal analysis and early detection issues in futures studies. While providing a broad view and discussing a variety of contributions on this topic, the aim of this article is to offer a more constructivist approach to early detection studies than has been typically the case so far. The article starts by positioning the underlying problem of weak signals within the broader field of futures studies. The second section examines the Ansoffian tradition, first on the basis of Ansoffs own contributions, then through key enhancements offered by scholars working in the same perspective. The third section develops the arguments for a constructivist critique of the Ansoffian tradition as a way to renew and enrich scientific debate. The fourth and final section presents the main open issues where research, case studies, methods and applications still need to make significant progress in the vast domain of weak signal analysis and early detection.