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 so as 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:
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.
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.
Arguably, humankind's earliest efforts at observations can be considered the harbingers of science―and its principles and methods. Until very recently, contemporary science―and scientists―held that routine monitoring (observations and measurements) could not be considered rightly as science. This likely was due to the notion that the practical, often operational, nature of monitoring was not considered to fit neatly within prevailing ideas of basic, hypothesis-driven, science. This view has changed substantially with the establishment of programs to explore, define and validate scientifically-defensible monitoring, observation and measurement activities. For example, the Environmental Monitoring and Assessment Program (EMAP), over the past 20 years has strengthened the science of monitoring. It has done this by investigating how monitoring can generate data and other information along with an understanding of the probability-based confidence that accompanies that data and information. It must be noted that the EMAP is a science-based, monitoring research program rather than an operational monitoring program.
Monitoring of nonprofit organizations is a vital topic and important component of accountability in nonprofit management. It is an essential component of concern to all large donors, philanthropic foundations, as well as in government granting and contracting. Over recent decades, concern for better measurements has been an essential concern in this context, under a variety of headings such as program evaluation, outcome assessment, performance contracting, social indicators and ratio analysis (nonprofit). Many nonprofit organizations are also involved in various forms of environmental monitoring as noted immediately above.