Integrated coastal management (ICM) has been considered worldwide to be a suitable approach to realizing comprehensive schemes to protect or develop coastal regions. A complex regulatory system stretching from international to local levels provides a framework for ICM practices. This raises the question whether and to what extent ICM practices have been supported by legal and policy frameworks at the international and national levels in different settings in both developed and developing countries. This paper examines four case studies in Germany, Costa Rica, Mexico and South Africa. Two research methods were used. First, a document-based analysis was conducted in two parts: a literature review of the content of ICM, and a policy and law analysis of the jurisdictions of the four case studies and at the international level (i.e., treaties and declarations). Second, a qualitative analysis was conducted based on in-depth interviews involving 21 decisionmakers representing all the case studies. With a view to enhance the effective use of international and national legal and policy instruments and their implementation in a more local site specific context, this study considers four principles currently guiding ICM practices: (i) incorporation of international instruments’ principles in national legal and policy frameworks, (ii) participation, (iii) sustainable development and (iv) monitoring. An I-P-S ((I) incorporation of international instruments’ principles in national frameworks, (P) participation (S) sustainable development) diagram is used for an integrative assessment of ICM and indicates directions for further improvements at the case study sites. The embeddedness of ICM into national legal and policy frameworks is a success factor for ICM, however, it is often limited due to a lack of implementation. Furthermore, ICM can easily be jeopardized if ICM is allocated a marginalized position.