For many years there has been concern about the social and working conditions of forestry workers in tropical countries, because their tasks are considered to be heavy work. There are two major aspects of forestry work in relation to which ergonomics can make important contributions. One of them concerns problems of adaptation to heavy manual labour. In these tasks, men using simple tools provide the most important part of the energy required to carry out given tasks. This can be quite critical, particularly when other factors are added, such as environmental heat. An alternative is represented by mechanized work, where human energy is replaced by machines. The workers become progressively more sedentary, limiting their activities to perceive and interpret information and to execute their decisions with actions that demand little muscular effort, but that require high participation by their mental processes. This corresponds to the direct relationship between the worker and the job. However, forestry work is performed in physical places where human beings can suffer the effects of heat, cold, noise, mechanical vibrations, and other factors. Furthermore, the psychosocial environment cannot be ignored. Problems may arise when workers have to stay in camps, not by choice but by necessity of the service they provide. In these cases, the camps become temporary homes, where workers have to stay for varying periods of time and where they have few options to choose their food, recreation and times for sleep. Facilities that promote hygiene, privacy and tranquillity are minimum basic conditions for a worker to recover and to start their next period of work in good physical and mental condition. In short, ergonomics provides an integrative approach to the analysis and solution of the problems that affect workers in their workplaces. Ergonomics has a constructive character that is essential for the incorporation of technologies for sustainable work. All these topics are analysed in this chapter.