Definition of sustainability

What is the only correct definition of sustainability?

Sustainability is the ability to meet the needs of the present without compromising the ability of future generations to meet their own needs.

WCED (1987). Our Common Future(PDF).

This is how we define sustainability and it is the only correct definition.


Notice how the definition is very specific about whose needs are to be met and for how long.

It explicitly includes the needs of everybody alive today, plus everybody who will ever live, until the end of time. There is no ambiguity.

Therefore, at its most basic level, sustainability can be defined as:

Mankind’s continued survival.

Incorrect definitions

Unfortunately, most dictionaries define sustainability very differently.

For example, one definition from Oxford Languages used by Google defines sustainability as the ability to be maintained at a certain rate or level.

incorrect sustainability definition
Incorrect sustainability definition

On the surface, this definition looks close enough to the one at the top. However, there is one crucial difference: the object is not defined. The ability of what/who?

In the correct definition the object is the present and future generations (as in “the sustainability of present and future generations”). The dictionary definition, however, leaves the object blank (as in “the sustainability of [whatever you want]”).

The problem with the dictionary definition is that the sustainability of [whatever we want] doesn’t necessarily guarantee our continued survival. In fact, it means just the opposite in some cases.

Example: “the sustainability of economic growth”

I am using this example, because it’s the one used by Oxford Languages above.

When we apply their definition, “the sustainability of economic growth” means continued economic growth. The implied question there is: How do we make the economy to grow?

However, when the object is the present and future generations, the question shifts to: What kind of economic growth will ensure our continued survival?

As the focus shifts, the answers will do, too.

Possible answerHelps economy?Ensures survival?
“Cut down more trees.”YesNo
“Catch more fish.”YesNo
Different questions produce different answers.

The problem with multiple definitions

Mixing definitions leads to misunderstandings, confusion or worse. Eventually, effective communication and finding viable solutions becomes impossible.

The solution

The only solution is to always double-check in order to ensure all parties are using the same (and correct) definition of sustainability and that everybody properly understands its meaning.