Regionalism in the Asia-Pacific shows peculiar features and distinctive patterns. Despite remarkable economic and political developments in the second half of the 20th century, the Asia-Pacific region remains slow in institutionalizing regional cooperation. Political rivalry, historical animosities, ideological tensions, disparities in levels of development as well as cultural differences have been identified as potential barriers to cooperation. (The rest is omitted.)

I. INTRODUCTION

II. REGIONALISMS IN APEC REGION

1. Economic Regionalism
1.1 Overview
1.2 Underlying Patterns and Characteristics
1.3 Potential Risks

2. Political Regionalism
2.1 Overview
2.2 Underlying Patterns of Existing Arrangements

III. “OPEN REGIONALISM” of APEC

1. APEC as New Regional Governance
1.1 Soft Regionalism
1.2 Vision-setting and Implementation
1.3 Broadening of the Horizon

2. “Open Regionalism” of APEC
2.1 Background
2.2 What does “Open Regionalism” mean?
2.2.1 The Second Report of EPG
2.2.2 Bergsten's Observation
2.2.3 “Open Sub-regionalism”

3. Assessments and New Challenges
3.1 Introduction
3.2 An APEC-wide PTA and “Open Regionalism”
3.3 Security Agenda and “Open Regionalism”

IV. CONCLUSION
1. Regionalisms in APEC Region
2. Challenges and Recommendations