Outlook and future perspectives

Characteristic trends in physics of nuclear clustering are discussed. Emphasis is put on the cluster structure physics because we have recently remarkable developments for this subject. As representative examples three points are discussed: (1) novel types of cluster structure in neutron-rich nuclei such as those formed by molecular orbits and dineutron correlation, (2) novel types of cluster structure in stable nuclei such as cluster gas states, (3) ab initio calculations of cluster structure. I also discuss some of new developments in other fields than nuclear structure. Various new phenomena and systems of clustering imply the basic importance of clustering dynamics in nuclear many body systems which give us rich prospects in future studies of nuclear clustering