This article explores the idea of unlearning on the basis of empirical data drawn from 73 social workers’ accounts of addressing their problems and challenges in critical action learning sets. To address intractable or wicked problems, characterized by having multiple stakeholders with competing perspectives and by an absence of obvious solution, it may be necessary first to unlearn existing responses and to ask fresh questions to illuminate what is as yet unknown. Action learning privileges questions over solutions in seeking learning from action on organizational challenges, whilst critical action learning is a variety that employs insights from critical social theory to promote critical reflection and unlearning in this process. The article breaks new ground in claiming: first, that unlearning in the context of the wicked problems of social work is characterized less by the discarding of outmoded knowledge and routines and more by a critical unlearning that opens up new possibilities of not knowing and non-action; and second, that critical unlearning is much more likely to take place when supported by a deliberated and social process such as that provided by critical action learning.