While alternative natural gas transportation technologies against currently available pipeline or liquefied natural gas (LNG) are expected to develop to be suitable for small and medium or remote gas fields, Mitsui Engineering & Shipbuilding Co., Ltd. (MES) has been studying natural gas hydrate (NGH) transportation chain and advocated at ICGH2005 the NGH chain was economical compared with conventional LNG system under some conditions. Meanwhile, MES has been carrying out research and development on the relevant technology development including construction of 600 kg/day class NGH production and pelletizing plants and a re-gasification facility and the process technology resulted from this R&D leads to the forthcoming demonstration plant of 5 ton/day production (under construction) to be dedicated to the demonstration project of small-lot NGH land transportation in western Japan. As the latest achievement, MES and Mitsui & Co., Ltd. (Mitsui) established NGH Japan Co., Ltd. (NGHJ) in April 2007, in order to study in detail on actual viability of NGH ocean transportation chain. NGHJ, MES and Mitsui have been conducting a practical feasibility study on certain cases in Southeast Asia in cooperation with 6 Japanese leading companies related to natural gas businesses. The study suggests that NGH chain was appropriate as a media for transportation from Southeast Asia to Japan and regional transportation within Southeast Asia in view of economics.