The focus of this study is the development of the Icelandic trawler fleet and the drivers behind the changes. The first stern trawlers began operation in 1970, five years later there were 58 fishing in the EEZ and in 1982 their number reached above 100. Excess capacity and overcapitalization characterized the demersal fisheries in the 1970s and 1980s, with the fishing effort increasing sharply. In 1984, Iceland implemented a system with partly individual transferable quotas (IQs) and in 1990 a uniform system of ITQs covering almost all fisheries. The past three decades the demersal sector has faced a reduction in total available catch (TAC). Therefore, the industry had to rationalize the fishing fleet and increase efficiency. These adjustments were not centralized by authorities, they were mostly left to the companies. The industry has in many ways adapted well. Part of the fleet was converted to freezer trawler in 1980s and 1990s. The ITQ system allowed the majority of ITQs to be almost freely transferable, which led to consolidation of fishing rights. Number of trawlers and companies have decreased almost constantly since 1995. Simultaneously, the industry focus has turned from catch quantity to value maximization aiming on product quality, making the industry more profitable. Since 2012, many of the stern trawlers have been renovated, but now the focus is again on delivering fresh fish instead of frozen at sea. The drivers behind these changes will be examined and related to status of fish stocks, markets and technological changes.