Here, I examine to what extend music and speech share processing components by focusing on vocal production, that is, singing and speaking. In shaping my review, the modularity concept has been and continues to play a determinant role. Thus, I will first provide a brief background on the contemporary notion of modularity. Next, I will present evidence that musical abilities depend, in part, on modular processes. The evidence is coming mainly from neuropsychological dissociations. The relevance of findings of overlap in neuroimaging, of interference and domain-transfer effects between music and speech will also be addressed and discussed. Finally, I will contrast the modularity position with the resource-sharing framework proposed by Patel (2003, 2008a). This critical review should be viewed as an invitation to undertake future comparative research between music and language by focusing on the details of the functions that these mechanisms carry out, not only their specificity. Such comparative research is very important not only theoretically but also in practice because of their obvious clinical and educational implications.