Agriculture has developed rapidly in the last 100 years and we cannot imagine modern farming without a tractor and other agricultural machinery. Both, Slovenia and Switzerland, are full of mountains and hills, and thats why accidents with agricultural machinery happens. Prevention of this events is crucial. Standard tractors are not good for steep inclines. Mountain tractors, mountain transporters, one or two axle harvester, all this machines have several features in common, such as low center of gravity, safety cabin, safety arc, safety belts and sits, very wide tires with a special profile, possibility of turning with all four tires, etc. Mountain mechanization is very spread out in Switzerland and they also have less accidents, due to overrolling with tractors. On the other hand Slovenia has a very poorly spreaded mountain mechanization and has more deadly accidents involving tractors and other agricultural mechanization. There are three key reasons for an accident to happen. First is the human error, which is responsible for 80 % of all accidents, because farmers have to much faith in themselves and their skills. Second is the environment. The main part of the environment is the ground. If it is too wet, shady or sunny, or if the incline is to steep there is a greater chance that something could happen. And the third reason is the mechanization by which we consider the equipemnt of tractors, their function, attachments and age.