Until very recently, recreational sea fishing was a blind spot in European and national fisheries policy. In Belgium, the sector has no landing obligation and is not subject to a licensing system, therefore, no information on the size of the sector, the landing data and the socioeconomic importance was available. In 2015, monitoring of recreational sea fishing activity was officially included in the national Programme of Measures to implement the European Marine Strategy Framework Directive. An obligation to collect biological data on recreational fish catches was also imposed at European level in the same year. In recent years, the Flanders Marine Institute (VLIZ) and the Research Institute for Agriculture, Fisheries and Food (ILVO) have developed a tailor-made methodology that provides a scientifically based answer to the above-mentioned knowledge gaps. This method mainly focuses on field observations and active participation from the recreational sea fishing community, in which transparent communication and mutual trust form the key values. The size of the recreational sea fishing community is estimated at around 2,900 individuals, 57% of whom are boat anglers. Two-thirds of the community lives in the province of West Flanders, while 7% of them live in Brussels or Wallonia. The average age is 56 years. The direct economic interest of the Belgian recreational sea fishing community is estimated at minimum €8.6 million annually. The indirect and induced economic value has not yet been determined, but it is expected that this will raise the economic importance of the sector above €10 million on an annual basis. Recreational sea fishing in Belgium is diverse in nature. Seven different techniques are distinguished within the framework of this study: (1) boat angling, (2) boat trawling, (3) angling from a dam/jetty, (4) angling from the beach/breakwater, (5) wading using a small shrimp net, (6) passive beach fishing and (7) horseback shrimp fishing. The spatial occurrence of these activities was mapped in detail by ...