Sustainability is a buzzword used in a number of different contexts with various interpretations attached.
If we are talking about macroeconomics, for example, it is used to refer to economic stability. If we are environmental activists, the word is then used to emphasize environmental consciousness. If we are just chatting with friends & complaining about our daily lives being not sustainable, what is often meant is simply a concern of continuity.
The question is: which one of these interpretations is true? All of them? None of them? Well, the answer is both, since all of them are indeed true but none of them provides us with a complete prescription of the popular yet misused concept - sustainability.
Historically, sustainability is closely related to the concept of sustainable development, which is the development that meets the needs of the present without compromising the ability to do so in the future.
This definition implicitly suggests that a sustainable system is not just present today but also a growing / developing one so as to be able to meet the needs of tomorrow. In other words, sustainability is the growth / development & continuity potential of a system.
"...the growth / development & continuity potential of a system..."
So, if we want a sustainable economy, stability itself is not sufficient but we also need economic growth. If we want to act environmentally friendly, we should not only focus on preserving our natural resources but also create new ones. If we want sustainability at our daily lives, we have to develop more talents, establish new social relationships, and generate more value.
In short, sustainability cannot be defined simply by continuity, environmental friendliness or economic stability. Instead, it is achieved by much more effort. This effort involves the consideration of three pillars - economic, environmental & social dimensions - simultaneously, which is referred to as triple bottom line accounting.
And from a similar perspective, achieving sustainability is also key for business enterprises given their growth / development & continuity potential is the top item in the agenda.