The author gives an exhaustive presentation of this church, which is a key monument for our knowledge of the architecture and painting of the late twelfth century. The main architectural type of the church has its roots in an earlier architectural form, that of the octagon type, imitating the katholikon of the nearby Nea Moni, dated in the mid-eleventh century. However, the monument employs new features, which stress the plasticity of the exterior, making it a forerunner of the Laskarid and consequently the Palaiologan era. Quite characteristic are the concealed-brick technique and the rich ornamental brickwork. The wall painting of the interior are dated to 1197, on the basis of epigraphic testimonies and the donor portraits of Eustathios Kodratos and his wife Pagomene in the narthex, as well as of Metropolitan Stephanos Pepagomenos, the founder's uncle, in the sanctuary. The iconographic programme in the sanctuary, naos and narthex is preserved in full and includes iconographic particularities, which in many cases have been established in Byzantine painting after the twelfth century. The completeness of the painted decoration and the exact dating of Panagia Krena to 1197 are two basic factors, which a priori allow a comprehensive artistic assessment of the Chian monument's frescoes in the broader context of Late Komnenian art. In addition, these factors make Krena a reference point for the study of mural painting in the eastern Aegean and, by extension, the Asia Minor coast, including understanding of the social background of this activity in the region and determining its formative influences.