The influential model of sentence production developed by Bock and Levelt (1994) posits two stages of grammatical encoding: functional processing and positional processing. This model is sometimes referred to as the “consensus model” of grammatical encoding, given its wide support within psycholinguistic research. However, most research in the cognitive neuroscience of syntax does not align well with this two-stage consensus model. We will review recent research on the neurobiology of syntax, focusing on lesion-symptom mapping in people with aphasia, and in particular on the agrammatism-paragrammatism distinction. We will illustrate how a two-stage model of grammatical encoding aligns well with this distinction but does not precisely match the processing levels of functional and positional processing proposed by Bock and Levelt. We will illustrate how this consensus model can be revised in order to better accommodate the data. Finally, we will evaluate extant models of syntax and the brain, illustrating their respective adequacy and inadequacy with respect to accounting for these phenomena as well as their poor alignment with the consensus psycholinguistic model. We argue that models which involve two stages of grammatical encoding are more fruitful for pursuing relationships between psycholinguistics, aphasiology, and neuroscience.