Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests and woodlands for associated resources for human and environmental benefits. Forestry is practiced in plantations and natural stands. The science of forestry has elements that belong to the biological, physical, social, political and managerial sciences. Forest management plays an essential role in the creation and modification of habitats and affects ecosystem services provisioning. A practitioner of forestry is known as a forester.

Modern forestry generally embraces a broad range of concerns, in what is known as multiple-use management, including: the provision of timber, fuel wood, wildlife habitat, natural water quality management, recreation, landscape and community protection, employment, aesthetically appealing landscapes, biodiversity management, watershed management, erosion control, and preserving forests as "sinks" for atmospheric carbon dioxide.

Forest ecosystems have come to be seen as the most important component of the biosphere, and forestry has emerged as a vital applied science, craft, and technology. The control of forests for timber production is known as silviculture, as practiced by silviculturists. Although forestry is a broader concept, the two terms are often used synonymously.

All people depend upon forests and their biodiversity, some more than others. Forestry is an important economic segment in various industrial countries, as forests provide more than 86 million green jobs and support the livelihoods of many more people. For example, in Germany, forests cover nearly a third of the land area, wood is the most important renewable resource, and forestry supports more than a million jobs and about €181 billion of value to the German economy each year.

Worldwide, an estimated 880 million people spend part of their time collecting fuelwood or producing charcoal, many of them women.^[quantify] Human populations tend to be low in areas of low-income countries with high forest cover and high forest biodiversity, but poverty rates in these areas tend to be high. Some 252 million people living in forests and savannahs have incomes of less than US$1.25 per day.

Over the past centuries, forestry was regarded as a separate science. With the rise of ecology and environmental science, there has been a reordering in the applied sciences. In line with this view, forestry is a primary land-use science comparable with agriculture. Under these headings, the fundamentals behind the management of natural forests comes by way of natural ecology. Forests or tree plantations, those whose primary purpose is the extraction of forest products, are planned and managed to utilize a mix of ecological and agroecological principles. In many regions of the world there is considerable conflict between forest practices and other societal priorities such as water quality, watershed preservation, sustainable fishing, conservation, and species preservation.

Dendrology is a subset of botany; it is the scientific discipline that studies woody plants (trees, shrubs, and lianas), specifically, their taxonomic classifications. Silviculture on the other hand is the commercial practice of forest management , primarily for the production of timber.

The provenance of forest reproductive material used to plant forests has a great influence on how the trees develop, hence why it is important to use forest reproductive material of good quality and of high genetic diversity.