Aim of the review was to provide a literature overview of the birth defects of cleft lip and/or cleft palate (CL/P).Through the use of the PubMed database items were collected that would provide information about the condition, leading to the discussion of the following topics: epidemiology, anatomical features, genetics, environmental factors, diagnosis and treatment.According to these data, the CL/P are the most common congenital malformations of the craniofacial region. There are different phenotypes and clinical features of this malformation, which differ according to the anatomical structures involved: cleft lip, cleft lip and cleft palate. The etiology is multifactorial and includes both genetic factors and environmental factors. For proper diagnosis and treatment it is important to complete a multidisciplinary approach to guide the patient from birth to the end of growth. Among the outstanding figures for the care of the anomaly are: the gynecologist, the pediatrician, the maxillofacial surgeon and orthodontist. Individuals with a cleft lip and/or cleft palate may experience problems in feeding, pronunciation, hearing and social integration, which can be corrected to a different extent by surgery, dental treatment, speech therapy and psychosocial interventions.Today the optimal treatment is difficult to find, because of the large variability of malformations and the subjective response of each patient to therapy.