The central argument for monitoring can be stated in a single sentence: You cannot recognize, understand, improve or maintain what you do not or cannot measure. The ability to measure is a necessity—an activity that we need to maintain our well-being and the quality of our lives. Also, this need places monitoring squarely in the context of achieving sustainability; it provides valuable tools that offer indicative measures of:

• Ecological and Environmental Resources;
• Economic Development and Growth; and
• Social Structure and Dynamics.

Purposeful, scientifically-defensible and credible measurements and observations in each of these areas can provide powerful bases for decisions and management actions that are focused upon a variety of goals including those related to sustainability. Broad categories of measurements arise from the practice of a spectrum of disciplines, not only those arising from environmental issues, opportunities and concerns.

Definition

The etymology of the term 'monitoring' derives from the Latin monēre: to warn (that is, “something or someone that warns, an overseer). Originally, in English, the definition of the term monitoring was limited to characterizing “someone who gives a warning so that a mistake can be avoided”. Now, it also connotes the act of observing something (and sometimes keeping a record of that observation; or to: keep watch; keep track of; keep under surveillance; or, check usually for a special purpose). With ever-increasing technological capability, the term can be used to describe a device (usually electronic) used to record, regulate, or control a process or system. Its meaning extends to keeping track of systematically (that is, on a regular or ongoing basis) with a view to collecting information. For example, to monitor the plant or animal populations of an ecological system or drinking water for impurities, to measure the condition of a nation's economy, or to monitor a peoples' social, political or cultural views or habits.