Recent acts of violence in Nice, France and across the world are a striking reminder of the shifting nature of terrorism.
"In the security world, we weren't surprised the guy got in a truck and ran through a crowd of people," Robert Corson, President of 360 Worldwide Security, concedes.
"The bad guys, the terrorists, they don't have a lot of tools at their disposal and they will use anything they can to conduct an attack."
As the face of terrorism evolves, how can travelers stay safe, both in the United States and abroad?
Corson cautions that terrorists are able to cause the most damage in unsecured areas with large crowds.
"Try and avoid the big landmark touristy places. There's a lot to see -- go out and see some of those other places, avoid those long lines," he suggests.
When booking a hotel room, travelers should also request rooms on the third through seventh floors, high enough to avoid violence on the street level yet low enough to still evacuate safely in the event of a fire.
International travelers should always register with the State Department to get safety alerts. Should an emergency situation arise, officials are able to communicate with registered travelers more easily.
It's also imperative that travelers make copies of important documents -- like passports and visas -- should the original documents be stolen or misplaced.
Above all, though, Corson advises travelers to exercise common sense. Be aware of your surroundings and attempt to blend in whenever possible.