The aim of my two-year research of environmental history is to scrutinise how the use of fish for food has evolved in Finnish society from the 1930s to the 2010s and what factors have contributed to this development. I focus on the cultural history of both the esteemed edible fish and the so-called rough fish. I analyse what turned some indigenous fish into valuable but endangered species and some into rough fish that are plenty, but little used for human consumption.