The recognition that attention performs two roles enables one to argue that the epistemology of attention is such that attention provides an immediate improvement to justification, as long as there are no defeaters, and also that suitably expert attention is sufficient for knowledge. Attentional justification is an underived epistemic principle, related to a view known as ‘Dogmatism’ in the epistemology of perception. There is cognitive penetration of attention by beliefs and interests, as well as by past actions, but it is restricted in scope. So attention improves justification, and sometimes, when attention is trained or cultivated, the improvement is such as to deliver knowledge.