Modern views on embryology have increased our understanding of the nature of oblique facial clefts. The anomalies that have their origin at the junction of facial processes, such as the nasomaxillary dysplasias, may be named primary clefts or transformation. The maxillary clefts that are due to a developmental arrest of the skeleton are in fact secondary defects of differentiation defects. The teratology of these malformations is discussed, and attention is drawn to the amniotic rupture syndrome as a possible cause. All these clefts are rare, their incidence ranging from 0.75 to 54 per 1000 common clefts. This author has been involved in the treatment of nine of these patients. Four had their malformation reconstructed with one of the conventional procedures described in the literature, but the results, although initially acceptable, soon deteriorated. A more aggressive approach was therefore chosen. Rotation and advancement of the cheek proved to be extremely effective and is now advocated as the procedure of choice. The transposition of a median forehead flap is considered an excellent alternative. Use of these procedures in five patients is reported. There were no complications.