More than two-thirds of artists are not paid for showing their work at publicly funded exhibitions, a survey of UK artists has found.
The poll of 1000 artists across Britain also found many of them have to turn down offers from galleries because they cannot afford to work for nothing.
A leading artists' organisation has said that unless artists are paid, in future galleries will only be showing "work by the privileged few who can afford to work for nothing."
In the survey, 71% of artists - from new ones to Turner Prize shortlisted painters and sculptors - got no fee at all for taking part in publicly-funded exhibitions over the last three years
The poll, which included many artists based in Scotland, also found that 59% did not have their expenses paid, and 63% of artists have had to turn down requests from galleries to exhibit their work because they cannot afford to work for nothing.
The survey comes days after the Fruitmarket Gallery in Edinburgh became involved in a row over its now-cancelled plan of using free labour to install a new exhibition by the artist Jim Lambie.
Susan Jones, director of A-N, the Artists Information Company, said: "The research shows the practice of not paying artists is deeply entrenched in gallery culture and presents a worrying trend in publicly-funded exhibitions."
She said artists have suffered a drop in income in the last few years and now earn an average of £10,000 a year.