In recent years, the ASEAN member states (AMS) made considerable effort to tap the vast renewable energy (RE) resources in the region. Several countries introduced feed-in-tariffs or regulations for RE as well as other supportive policies, for example tax and customs exemptions or tax holidays. Despite those efforts and some promising developments, a large scale market for RE applications has not yet been in place in the region. In particular, complex administrative procedures, lack of transparency in the project cycle and permitting procedures as well as insufficient access to financial resources can be identified as important obstacles to an effective market and industry development. The ASEAN RE Guidelines are developed to facilitate increased private sector activity and investment in the RE sector of the ASEAN region. Since the confidence of project developers and investors is prerequisite to boost region-wide RE deployment, the provision of transparent project development and permit procedures is indispensable.