Abstract. This paper presents some of the first results of a project at the Scottish Agricultural College in Edinburgh which is investigating skin strength in potatoes. These first results highlight how little we know and how much more there is to learn about skin adhesion strength in potatoes, especially about the mechanism of skin set, however, a number of general conclusions can be made. It is perhaps only when there are large differences in a characteristic such as skin thickness. The second is that we are now looking more closely at changes in the zone of separation, such as water content, changes in biochemistry of substances, such as pectins. These are probably more important. Overall, between haulm destruction and harvesting we estimate a force of 15-20 N is equivalent to the thumb test when skin is set.