For greatest effect, indicator data should be linked to pre-established criteria in the management cycle, and tied to potential management actions. For example, if a series of satellite images indicated that the rate of decline in area of old-growth forest exceeded a threshold (say 1%/yr), this might raise an alarm and lead to logging reductions. Much as operational control criteria signal the need for adjustments in an industrial process, environmental indicators should monitor changes in, or impacts on, environments and point to the need for responses.

Often, indicator data will require sophisticated interpretation, such as through extensive statistical analyses, computer modelling, or expert assessment. Evaluation of potential management actions typically involves a variety of inputs, of which indicators are just one.

A range of tools and expertise can be used to select and focus this data pool on a particular management objective. Thus, deciding whether to respond to an algal bloom, and, if so, which remedial actions to take, will depend on more than mere indications of its presence. Other indicators may give insight into the state of water quality; additional sampling could establish the species causing the bloom; or an expert might provide an interpretation not available by other means. Indicators effectively point to the need for action - but other information is often needed to confirm this and to shape the responses.

Various means are employed to boost the power of indicators to convey the nature of a situation or trend. Communication to managers is the essential function of indicators. They can also convey information to a wider audience telling them, amongst other things, whether management of aspects of their environment is effective. So, the power to communicate and report is one factor to be considered in choosing, designing, using and interpreting indicators.