The present study comparatively analyses local and supra-local strategies for sustainable development of multifunctional fen landscapes in Germany (five strategies), the Netherlands (six strategies) and the UK (seven strategies)—thereby filling a gap in the existing academic literature. Fen landscapes have a peat soil which may be irreversibly lost once decomposed. These landscapes are currently under pressure due to drainage and land-use changes. A variety of strategies is applied and no particular type of strategy dominates in efforts to achieve sustainability. Such variety may be explained by differences in national policy contexts, decision-making and designing traditions, and, views on urgency and priorities of sustainability issues. Yet, the landscapes of our research focus exist in the organized mutual context of the European Union. Our study provides essential characteristics of steering interventions, to be considered by European policy-makers, when supporting initiatives for sustainable development of these landscapes. These include: focus on slowing down peat loss by reserving about 20–30% of an area for rewetting and/or nature conservation; development of a long-term vision; facilitation of a fair, transparent, inclusive and careful negotiation process on goals, means and sacrifices.