Compared to premise control and implementation control, strategic surveillance is designed to be a relatively unfocused, open, and broad search activity.
"... strategic surveillance is designed to monitor a broad range of events inside and outside the company that are likely to threaten the course of the firm's strategy."
The basic idea behind strategic surveillance is that some form of general monitoring of multiple information sources should be encouraged, with the specific intent being the opportunity to uncover important yet unanticipated information.
Strategic surveillance appears to be similar in some way to "environmental scanning." The rationale, however, is different. Environmental, scanning usually is seen as part of the chronological planning cycle devoted to generating information for the new plan.
By way of contrast, strategic surveillance is designed to safeguard the established strategy on a continuous basis.