NeoFirthian theories which include Systemic Functional Linguistics and its congeners have unlike other functionally oriented theories engaged minimally with linguistic typology and have made little impact on the wider discipline. This book offers a programmatic and NeoFirthian informed typological investigation that points to potential mutual enrichments of linguistic typology and NeoFirthian theories.ampnbspOn the one hand this book identifies the inadequacies of the dominant atheoretical approaches to linguistic typology and shows how these can be circumvented through a firm foundation in a NeoFirthian theoretical framework. On the other hand it contends that NeoFirthian approaches must take typology seriously as a criterion of theoretical adequacy and be able to account for the full range of grammatical phenomena and their variation across languages as well as those features that are universal. Case studies illustrate this argument through a selection of grammatical phenomena in particular grammatical relations the noun phrase complex sentence constructions optional case marking and grammatical classification.ampnbspThis book will be of interest to typologists as well as to linguists working within Systemic Functional Linguistics and other functional theories.