Selecting and sequencing linguistic representations is a necessary component of sentence production. Damage to the left frontal cortex might impair this process, leading to non-fluent production in aphasia. In this talk, I will describe behavioral and neuroimaging studies with stroke patients and healthy adults that shed light on the neural substrates underlying selection/sequencing. The results inform our understanding of the role that general cognitive mechanisms play in language and possible sub-specialization within those mechanisms.