When someone believes something that is justified for her, what part does the subject play in her state of being justified? I will answer this question by developing a strong internalist account of justification according to which the justification of a believing for a subject consists in her having grounds for her belief, and holding the belief in recognition of those grounds. But the internalist theory I defend incorporates key elements of reliabilism into its account. Using perception as a model for justification, I show how ordinary perceivers would appeal to external factors to support their perceptual beliefs, and normally suppose that their beliefs are reliably connected to the objects their beliefs are about. I find in this feature of our common justificatory practice a sufficient basis for positing an externalist condition on justification—namely that subjects are only justified if their beliefs are reliably connected to their objects.