The article calls for a shift in organizational theory towards prospective theorizing, which involves imagining desirable futures. This approach moves away from traditional, past-oriented theorizing and instead focuses on envisioning and creating future-oriented, values-based theories. The authors argue that current theories are too focused on empirical past data and fail to address the urgent challenges of the present, such as climate change and social inequality. Prospective theorizing requires a shift in both onto-epistemological and axiological orientations: from projection to imagination, and from values-neutral to values-led theorizing. This shift allows for more imaginative and values-based approaches to theorizing, which can help create more sustainable and equitable futures. The authors propose four modes of theorizing the future: projected factual futures, imagined (counter-)factual futures, projected desirable futures, and imagined desirable futures. Each mode represents a different approach to theorizing the future, with the latter being the most ambitious and radical. The authors also develop the concept of speculative rigour, which includes criteria such as generative potency, process transparency, plausible desirability, and speculative plausibility. These criteria help evaluate the quality of prospective theorizing. The article emphasizes the importance of moving away from traditional, empirical-based theorizing and towards more imaginative and values-based approaches. This shift is necessary to address the complex and urgent challenges of the present and to create more sustainable and equitable futures. The authors argue that prospective theorizing can help create new tools and approaches for theorizing what does not yet exist, and that this approach can help move towards a more regenerative and values-based form of scholarship. The article calls for a more rigorous and imaginative approach to theorizing, one that is grounded in values and focused on creating desirable futures.The article calls for a shift in organizational theory towards prospective theorizing, which involves imagining desirable futures. This approach moves away from traditional, past-oriented theorizing and instead focuses on envisioning and creating future-oriented, values-based theories. The authors argue that current theories are too focused on empirical past data and fail to address the urgent challenges of the present, such as climate change and social inequality. Prospective theorizing requires a shift in both onto-epistemological and axiological orientations: from projection to imagination, and from values-neutral to values-led theorizing. This shift allows for more imaginative and values-based approaches to theorizing, which can help create more sustainable and equitable futures. The authors propose four modes of theorizing the future: projected factual futures, imagined (counter-)factual futures, projected desirable futures, and imagined desirable futures. Each mode represents a different approach to theorizing the future, with the latter being the most ambitious and radical. The authors also develop the concept of speculative rigour, which includes criteria such as generative potency, process transparency, plausible desirability, and speculative plausibility. These criteria help evaluate the quality of prospective theorizing. The article emphasizes the importance of moving away from traditional, empirical-based theorizing and towards more imaginative and values-based approaches. This shift is necessary to address the complex and urgent challenges of the present and to create more sustainable and equitable futures. The authors argue that prospective theorizing can help create new tools and approaches for theorizing what does not yet exist, and that this approach can help move towards a more regenerative and values-based form of scholarship. The article calls for a more rigorous and imaginative approach to theorizing, one that is grounded in values and focused on creating desirable futures.