This volume is dedicated to the field of Specific Language Impairment (SLI), addressing important research questions, including: the interrelation of genetic and cognitive profiles of individuals with SLI; the comorbidity issue and clinical boundaries between SLI and other developmental disorders; cross-linguistic manifestations of SLI; and theory-motivated therapy approaches to individuals with SLI. This volume brings together researchers with different scientific backgrounds and research disciplines, challenging current points of view and offering new perspectives on issues of SLI and developmental disorders.