Evidence-based LKGSF diagnostics "LKGSF complex" is the first German-language evidence-based inventory for speech therapy diagnostics in cases of cleft lip, jaw, and palate deformities. It includes diagnostic components that can be applied individually or in combination: basic diagnostics, orofacial diagnostics, phonological-phonetic analysis, and assessment of the participation level of children and adults. Clear forms for compiling results and documenting therapy progress make the material indispensable for working with LKGSF patients from infancy to adulthood. Communication forms facilitate the exchange of medical information. "LKGSF complex" is aligned with the ICF and internationally recognized diagnostic standards.