The purpose of this thesis was to study investigate the social networks of forest machine drivers, what factors had an effect on them and how the forest machine drivers felt. A personal interest of the researcher led to the selection of this topic. The thesis was conducted in an office environment as well as in the field. The research method was semi-structured interviews. All the interviewees were presented the same questions, with the answers not tied to choices from a list. The interview questions were designed to find out where forest machine drivers (harvester and forwarder) stand on the purpose of this thesis.

The collection of the research material was easy as there was a lot of source material available. Most of the theory was searched from the internet or Antti Skyttä´s book Tiimiytys ja sen läpivienti, which was published in 2005. Mutual employment pension insurance company Etera's work welfare guide and Metsäteho Oy’s materials were also valuable sources for the thesis.

The results of the thesis show that the social network of forest machine drivers overall is on a good level. They have contact with about three to six people per workday. These people are usually the closest work friends or the management of the company. Forest machine drivers considered themselves as social people who have enough social communities. A lot of the drivers did not acknowledge themselves as belonging to a group and that is why the feeling of belonging to a group was only on a satisfiable level. It is satisfactory to say that the thesis met its purpose. In addition to a comprehensive theory base, successful semi-structured interviews and with the aid of forest machine drivers with diverse backgrounds, quite a comprehensive picture of the social network of the forest machine drivers was gained.