The Good Fish Foundation is initiator and owner of the VISwijzer. The assessments on the VISwijzer are based on the most recent, scientific data on fish stocks. Apart from that, data from the World Wildlife Fund, Fishbase and the Food and Agriculture organization of the United Nations (FAO) is used. The assessments on the VISwijzer are updated every year. 

The assessments are done for every species. There is a seperate questionnaire for wildcatch and aquaculture. The questions are focussed on sustainability and the environment. Points are given for each question. The total amount of points decides what the final assessment is, which is displayed in the colors green, yellow or red.

– A fish species gets a red score if the final assessment is between 0% and 40%
– A fish species gets a yellow score if the final assessment is between 40% and 60%
– A fish species gets a green score if the final assessment is between 60% and 100% 

Aspects of the wildcatch questionnaire

– Biological characteristics of wildcatch: How well can a species recover from being caught?
The effects of fishing and fishing techniques: Is there alot of by-catch? Is the fishing technique used harmful for the environment?
The effects of the management: Are fishermen and governments taking measures and are these measures effective?

Aspects of the aquaculture questionnaire

– Sustainability of source usage (sustainability of the fish food and a sustainable production system): How much water and energy is used in the production system, how sustainable is the fish food and how much food is needed per fish.
– The effects on the environment: Is there water pollution and are diseases spreading easily? 
The effectiveness of management: Is the farmer following the laws of the government or is the farmer taking action on it’s own to make his farm more sustainable?