Arrive early for a rendezvous, scout the setting, remain in control of your environment—and have an exit ramp.
When you arrive for a meeting with a source, anything can go wrong.
A two-timing source could set you up. Or you could be set up by a rival intelligence service.
In other words, it is dangerous.
The solution is situation awareness.
Do not accede to a source’s choice of location, but if you must, scout it beforehand.
Ideally, choose the location yourself, somewhere in public and which you have already visited, chosen for its appropriateness based on security and contingency options.
Arrive thirty minutes before rendezvous time. Observe the meeting place from an obscured position, watch for anything unnatural or suspicious. When your source has arrived, approach with caution.
Know in advance, if you must flee, how best to do so.
Any back exits? Do buses pass by? Where is the nearest subway station? Any department stores or hotels you can slip into and lose yourself?