Vehicular surveillance and foot surveillance each have their challenges, but they share a common objective: to be invisible by hiding in plain sight. I’ve done plenty of both and tend to enjoy foot surveillance the most—mainly because I like the freedom of not being confined to a car.

The success of any surveillance operation relies heavily on preparation. And a good surveillance operative should be ready to go from mobile vehicular to foot surveillance at a moment’s notice. You might be riding along with another investigator as a passenger, ready to jump out and follow on foot. Or you might be following a subject by public transport—which means that surveillance on foot is your only option.

If you suspect that you’ll be on foot for all or part of the job, plan accordingly. Choose clothing that blends well into the places you’re likely to go (and is weather-appropriate), carry lightweight recording equipment that won’t attract attention (including your smartphone), and review the local transport system thoroughly.

Once you arrive at the initial assignment location, canvass the area for surveillance cameras, security guards, or anyone who might notice your activities (such as a doorman). Check for all possible exits from the location under surveillance, and choose the best possible observation post.

From there, don’t just watch the exit(s); keep assessing the whole area, and planning how you might follow your subject(s) once they appear. Is the area busy enough with foot traffic for you to follow closely on the same side of the street, or should you stay further back, or even cross the street to follow? You may be in a busy area, but if there aren’t many pedestrians, you’ll have to maintain your distance. You don’t want be too close, as illustrated in figure 1, without any cover.

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