Over the past century the values that society has placed on forests have changed in both emphasis and scale.

• In recent decades there has been greater emphasis on the sustainability of specific values, such as species diversity, wildlife habitat, soil and water conservation, recreation and cultural values, and carbon sequestration.
• Many of the values receiving increased attention must be considered at relatively large spatial and temporal scales (e.g., regional, continental, and global biodiversity).

The Montreal Process Working Group developed a list of criteria for sustainability. These provide a robust set of values for considering how to make forests sustainable. The criteria are:

• Biodiversity -- Montreal Process
• Forest productivity
• Forest Health
• Water and Soil Conservation
• Carbon Storage
• Socio-economic Conditions
• Infrastructure

The objective of sustainable management is to maintain all of these values in all forests at all times. This requires that each forest type provide its “fair share” of each value in relation to other forest types and regions, as well as to future generations.

However, the values provided by forests are not equally distributed among forest types or regions. Biodiversity is a good example. The majority of the global terrestrial biodiversity is concentrated in tropical forests, which are found in economically underdeveloped countries; in contrast, biodiversity is typically low in temperate zone forests -- most of which are in economically developed countries.

Improvements in transportation and communication abilities have led to the establishment of efficient global marketplaces. As a consequence surpluses of wood and wood products from one region might be able to offset shortfalls in other regions. For example, Asia consumes approximately 215 million m³ more industrial roundwood than it produces, but because of efficient and inexpensive global transportation it can import wood from Africa, Europe and the Americas, all of which harvest and process excess industrial roundwood. Other regions produce more wood than they consume; in general, however, the balance between production and consumption is quite close in most regions. Of course, not all forest values are as easily transported as wood and wood products.