Preparation, design and implementation of two Fish Farmer Field Schools in Sidoarjo, Indonesia Project contextIn the regency of Sidoarjo, a coastal area of approximately 15,000 ha, thrives on aquaculture practices. That coastal landscape with ponds is located in a mostly flat delta with sparse corridors and galleries of mangrove trees along waterways, and sparse green belts at the coastal front. However, the transformation of a formerly open mangrove landscape in one dominated by ponds with limited water exchange has unexpected consequences: sediment accumulates in rivers, creeks and canals, and in front of rivers’ outlet. These changes contribute to upstream flooding and impact the salinity levels. According to the study Improvement of aquaculture systems in Sidoarjo, finalized in 2023, mangrove expansion (and conservation) is key to coastal landscape management. Such nature-based-solutions (NBS) can contribute to decreased flooding upstream and improved daily water flow, sediment evacuation and salinity levels. For the ultimate NBS solutions the support of the coastal communities is indispensable.One of the recommendations of the above-mentioned scoping study was to pilot Aquaculture Field Schools, also called Fish Farmer Field Schools (FFFS). These seem more fit than other learning approaches to create awareness on the need to integrate, and the capacity to implement, NBS approaches into current aquaculture practices (See also below). The present training programs of the Marine and Fisheries Agency (Dinas Kelautan dan Perikanan = DKP), ATINA and KOIN (Konservasi Indonesia, an NGO under ATINA), are mostly trainer-centred and focus on transmitting knowledge on aquaculture. The FFFS use farmer-centred learning, are embedded in the communities, and have demonstrated to be more effective in promoting NBS.The curriculum adjustment for the FFFS should focus on integrating NBS into current aquaculture practices. Lessons learned from this case study will be disseminated to support the uptake of NBS in Indonesia and worldwide. This is especially relevant for Indonesia where development of silvofisheries, combining mangrove and aquaculture, is expected to cover 70% of the national mangrove rehabilitation program of 75,000 ha in four provinces between 2024-2028.In addition, the FFFS can serve as a stepping stone to gathering relevant users within an estuary system and as one of the enablers towards a landscape-integrated NBS approach. As such, it links to broader ambitions and aligns the thematic focus of bilateral cooperation between Indonesia and the Netherlands.AmbitionTo create know-how, awareness and capacity on the contribution of NBS to improving both aquaculture and water quality issues in two local communities as well as in the regency’s institutions and organisations related to aquaculture. The latter are aware of and engaged in plans to support pilots of two NBS solutions related to the polyculture of tiger shrimp and milkfish: (1)	make large storage, i.e., treatment ponds for brackish water; (2)	transform a pond’s section along the waterway into a greenbelt of mangroves.ScopeThe scope of work consists of three phases:1.	Preparation of the FFFS, including, among others, an assessment of the potential for improving the existing organic aquaculture practices that are threatened by reduced salinity levels in the water, and tailoring the curriculum to the local context in consultation with the local stakeholders.2.	Implementation of two community-based FFFS, one in the cluster of Sedati and the other in that of Jabon. The clusters are separated by the Kepetingan River.3.	External communication through the development and dissemination of experiences and knowledge products.