Illegal, Unreported, and Unregulated (IUU) fishing can take place in all capture fisheries, whether within national jurisdiction or n the high seas. Efforts to conserve and manage fish stocks are undermined by IUU fishing and can lead to the collapse of a fishery or can seriously impair efforts to rebuild fish stocks that have already been depleted. This may lead to the loss of both short- and longterm social and economic opportunities and could have a negative impact on food security. Every country in the Southeast Asian region is always confronted by increasing pressure on their fisheries resources from illegal fishing. In many cases, IUU operation is more related to the lack of MSC management. Nevertheless, countries in Southeast Asia should now focus on developing preventive measures in achieving sustainable fisheries rather than on fisheries management that focuses on mitigating resource conflicts. Such measures could include regulating the number of fishing vessels and overcapacity as well as an effective right-based fisheries system. The IUU concept, with more focus on illegal fishing, undermines national and regional efforts to conserve and manage fish stocks and, as a consequence, inhibits progress towards achieving the goals of long-term sustainability and responsibility. Moreover, IUU fishing greatly disadvantages and discriminates those fishers that act responsibly, honestly and in accordance with the terms of their fishing authorizations. This is a compelling reason why IUU fishing must be dealt with expeditiously and in a transparent manner. If IUU fishing is not curbed, and if IUU fishers target vulnerable stocks that are subject to strict management controls or moratoria, efforts to rebuild those stocks to healthy levels will not be achieved.

The problem of the coastal and marine fisheries in the region lies in the depletion of fish stocks, overfishing, conflicts between many resource users, ignorance, violations of laws and regulations by fishermen, etc. Certain countries are making strenuous efforts to improve their fisheries management and improve their MCS systems. Some are successful while some have failed, which might be due to the nature of the fishery resources being common property, lack of strict implementation of limited entry policy and other policies, shortage of manpower and equipment to enforce the laws, lack of coordination between the government agencies concerned, etc.

It can be understood that no MCS activities will be successful if there is absence in understanding and acceptance by the fishers of the rationale behind the MCS actions being implemented. Other measures are also needed to help increase compliance from the fishermen. Thus, in combination with MCS activities, such measures as establishing community-based fishery management, providing information to increase awareness among fishermen and their family members of fisher conservation and responsible fisheries, establishing voluntary groups, providing training programs for students, etc. are still necessary. It is expected that these measures will help encourage fishermen to operate more responsibly in the long run. Eventually, MCS as defined under the Southeast Asian context could be one of the important fisheries management tools in order to achieve sustainable fisheries in the region.

During the past ten years, the Southeast Asian countries have focused their efforts towards the promotion of sustainable fisheries management and the implementation of countermeasures to address IUU fishing. At a regional level, SEAFDEC has been promoting the development of regional tools and supporting ASEAN Member States (AMSs) for combating IUU fishing, such as ASEAN Guideline forPreventing the Entry of IUU Fish and Fishery Products into the Supply Chain, the Regional Fishing Vessels Record (RFVR), ASEAN Catch Documentation Scheme, Regional Cooperation for Implementation of Port State Measures through Strengthening Sub-regional Cooperation to Enhance the Implementation of MCS in the region which concerns among others, the adoption of efficient MCS system for effective control of fishing capacity and combat illegal, unreported and unregulated (IUU) fishing, destructive fishing, and encroachment by larger fishing vessels in coastal waters. Therefore, to strengthen and update information on MCS for combating IUU fishing through finding the need for capacity building which relevant MCS will be conducted via The Regional Workshop on Monitoring Control and Surveillance for Combating IUU fishing in Southeast Asia.