True protection is about risk analysis and careful preparation. It's about transforming what protection specialist Mark Fair calls a 'sheep' (a target who doesn't vary his movements, and hasn't considered his vulnerabilities) into a 'tiger' (one who is unpredictable in his patterns and minimizes his exposure). Photo-dramatization photographed by Stephen Voss for WSJ.Money

MIDWAY THROUGH AN evening party at the French Embassy in Washington, D.C., my date and I encounter a strange and off-putting man. He's edging closer, awkwardly trying to horn in on our conversation as we mingle by the pastry chef's table. There's something disconcerting about him. Chances are he's harmless (if also charmless). But what if he's not? What if he's more than merely annoying? What if he has bad intentions?

Now, raise the stakes: Imagine I'm the CEO of a large company. I've recently laid off thousands of workers and, unbeknownst to me, this man was among the pink-slipped. He's frustrated and angry. He's somehow gotten his hands on a copy of my daily schedule. He knows I'm slated to make an appearance at this party, and he's spent his last dollar on a ticket to get in. He's about to impose himself on my life in some way. Maybe it's just a loud verbal tirade in my face. Or maybe it's something much worse.

Interactive: Security Detail

Photos: Secrets of a Security Specialist

Click to view slideshow Photo-dramatization photographed by Stephen Voss for WSJ.Money

Situations like this are why executives and many other well-off individuals hire protection specialists like Mark Fair. Fair is at this embassy party too, standing several feet away in an inconspicuous manner. (Remarkably inconspicuous, given that he's a 240-pound, extremely muscular guy in a suit.) Should anything go awry, Fair will instantly close in and—with minimum fuss and maximum efficiency—separate my date and me from this weird fellow, spiriting us away to safety.

Fair is trained in the nuanced art of providing close-in protection for CEOs, royalty, dignitaries and the wealthy. A former Marine who was deployed to locations including Liberia and southwest Asia, Fair went on to spend 15 years at the global security outfit GardaWorld before launching his own Maryland-based firm, The Modad Threat Management Solution. I met him in Washington and asked him to treat me as he would a client.

First, we discussed what sort of threat scenario I have in mind. Different threats call for different models of protection. A group of high-profile executives traveling to a dicey region of Venezuela might require armored cars and a dozen specialists toting assault rifles. A controversial television personality addressing a crowd of fans in Dallas might need the company of only one or two unarmed (if hefty) individuals to deter any disgruntled viewers from tossing a pie in her face.  

Fair and I decide, for the purposes of this exercise, that I am a Midwestern executive traveling to Washington for a public event. Perhaps my company has recently been blamed for an environmental disaster, with activist groups condemning me personally. There's no specific threat against me—no anonymous letter threatening acts of violence—but it seems quite possible that radical activists might want to confront me, embarrass me or even harm me.

You might imagine Fair's job is simply to stand by my side, look intimidating and intervene if anyone accosts me. He disagrees. "That's reacting," says Fair. "That's being a bag of meat behind the principal's shoulder."

True protection is about risk analysis and careful preparation. It's about transforming what Fair calls a "sheep" (a target who doesn't vary his movements, and hasn't considered his vulnerabilities) into a "tiger" (one who is unpredictable in his patterns and minimizes his exposure). When done right, reaction rarely becomes necessary. You, not the bad guys, are dictating the course of events. "No one wants to go after a tiger," says Fair. "If I'm a bad guy, I go after the sheep when I know he's going to be watching his son play tennis."

The day before our mock security detail, Fair walks me through his advance work. He checks my itinerary—including a lunch meeting, a visit to a museum and the evening embassy event—and plots it out on a map, noting the choke points along the driving routes where my hired car will be most vulnerable to an ambush. He knows the ins and outs of the local private airports. He considers the best escape routes, in case we're forced to evade an attack. He has memorized the precise locations of key hospital facilities and the quickest way to reach them, in the event that emergency medical treatment becomes necessary.

Zeroing in on the specific venues on my schedule, Fair then gets down to the crucial nitty-gritty of preparation. We pay an advance visit to every spot, going over each with a fine-tooth comb. A principal is most vulnerable during transitions—walking between a car and a building entrance, or vice versa—as the assailant needn't overcome the extra obstacles provided by an armored vehicle or a building's control and security systems. So Fair carefully assesses the "apron"—the area between the sidewalk curb and a building's front door—to choreograph how he can get me in and out smoothly. He even checks the curb height to ensure the car door will clear it, avoiding a snag that could slow us down. He might have the car drop me off at one entrance and then pick me up at a different exit, to be less predictable.

At the Palm, the venerable D.C. steakhouse where I'll be having my lunch meeting, Fair strolls in during a quiet afternoon shift and takes the measure of the space. He decides he'd prefer I sit at a table far from the kitchen door, with my flank protected by a wall. Meanwhile, he plans to take up a position near the bar, sipping water at a spot where he can keep an eye on me while also clocking the front and rear entrances. At one point, the restaurant's general manager walks over and—once Fair has explained that he's doing advance security work for a lunch meeting tomorrow—offers to let us pull our car straight into the basement garage and make our entrance through the kitchen. "We deal with high-profile people all the time," he assures us.

At every step, Fair has his eyes peeled for anyone who might be surveilling us, so he can get a jump on preventive measures. He looks for people who remain motionless among a generally active crowd. He checks for hands in pockets, bulges in suit jackets. Is that a real taxi? Or are its door decals just slapped-on stencils, providing clever cover for someone to idle at the corner while observing us?

The A-list type doesn't want to draw attention. They go out the back of a nightclub, through as many as 12 doors, through a kitchen, to a waiting limousine. They want zero hype, and their security team needs to blend in.

THOUGH MANY COMPANIES and wealthy individuals curtailed their security spending during the recession, the private-contract security-services market in the U.S. has grown 5 percent since then, to $28.2 billion, according to research firm IBISWorld. Globally, the United Nations has said, the industry is poised to reach $244 billion by 2016.

Many large companies, of course, have their own chief security officers and protective teams. But there is only so much they can handle, so they typically limit their services to a select level of officials. In many cases, when their executives travel, they'll augment their teams with agents from local private security firms that know the roads, customs and language, and that perhaps can provide experts licensed to carry a firearm there. Smaller firms and wealthy individuals may not have full-time security operations, instead hiring on an as-needed basis.

But private security can mean different things to different people. Is it a rent-a-cop who shows up on the morning of an event and asks what his role is, or a squad of ex-special-ops soldiers who train together for weeks in advance, establishing communications protocols and working in shifts? Sometimes even clients don't know what constitutes good protection.

"We deal with two types of principals," says Steven Striker of Striker VIP, a Las Vegas-based concierge and security firm that employs up to 20 specialists. The celebrity or A-list type, for example, doesn't want to draw attention, he says; they go out the back of a nightclub, through as many as a dozen doors, through a kitchen, to a waiting limousine. "A-listers want zero hype, and their security team needs to blend in," he says. But the B-listers are different. "They're looking for cameras," he says. "They want to be on the red carpet with a big, ominous Samoan guy at their side." Many experienced specialists scoff at this style of celebrity protection—the thug-with-sunglasses-and-an-earpiece model— as more about image than actual safety.

Not surprisingly, security pros say, clients do sometimes get in the way, thwarting the efforts of their own teams. But these teams have failed of their own accord too, which hasn't gone unnoticed in cases where cameras were hovering. Some critics have noticed celebrities swamped by unruly mobs at U.S. airports, for instance—a situation that can often be avoided by using VIP doors. "It looks like a clown show," says Bob Oatman, president of the executive-protection training and services firm R.L. Oatman & Associates, referring to one high-profile example.

In 2011, a stalker attacked Paris Hilton's male companion as the couple walked outdoors, circled by paparazzi. Hilton's bodyguard tackled the stalker to the ground, put a knee in his back, and restrained him—but critics say that might have left Hilton, who had drifted a few yards away in the chaos, briefly unprotected. "The first attack could have been a decoy," says Jason Hanson, founder of Concealed Carry Academy, a security-training outfit in Cedar City, Utah. He says the guard might have instead stunned the stalker with a martial arts chop, and then evacuated his client. A Hilton representative declined to comment.

Other failures can lead to graver consequences. It's difficult to compare presidential-level security teams to smaller private details, but many protection specialists find useful lessons in the 1981 assassination attempt on President Ronald Reagan. Experts say the initial failure was allowing assailant John Hinckley Jr. to get too close with a weapon—the U.S. Secret Service now requires much tighter cordons. But the reactions of the law-enforcement officials on the scene are telling. "The police officers first duck for cover and then go after the assailant," says Fair. "But you see the Secret Service guys employ totally different techniques. Agent [Timothy] McCarthy makes himself big and gets in front of a bullet. Another agent grabs Reagan by the belt and shoves him in the car." The president, not his attacker, was their focus.

Max Milien, a spokesman for the U.S. Secret Service, says that although the agency won't discuss details, changes have since been made in the handling of arrivals and departures of presidents, such as "the increased use of magnetometer," an instrument that detects the possibility of explosives. "Supervisory oversight of protective trips and events has increased greatly since 1981."

COSTS OF PRIVATE SECURITY can vary widely but reach as much as $1,500 a day for an expert specialist. That doesn't include travel expenses (if there's a trip involved) or extras such as armored vehicles. An American bank executive traveling to Israel who might require two armored cars, four specialists and a week's stay at a five-star hotel would spend about $30,000, experts say.

Security pros say cost-cutting, of course, is tricky. Some clients rein back on advance work fees, while others hire just one protective specialist after their security firm advises them that up to three would be stronger. Working alone while protecting a principal is sometimes dubbed "the witness formation" by pros, who fret that when solo they might be more likely to witness an unfortunate event than to be able to prevent it. Some blame the 1998 incident in which Bill Gates took a pie to the face on Gates's lack of personnel. Video of the event reveals that he had no guards in front of him as he was frontally assaulted while walking toward a building entrance. A spokesperson declined to comment. 

Best-selling author Brad Thor has received numerous anonymous threats, some in response to his book "The Last Patriot," which presented controversial theories about Islam. He wasn't willing to face those threats on his own. "I knew to take the death threats seriously," says Thor, whose book tours are held in public and announced months in advance. Thor hired Oatman to provide his security, which has included rolling through Mexico in multiple armored Suburbans during a perilous reporting trip, keeping watch outside Thor's home and thwarting pranksters who hoped to embarrass Thor at an event. In looking for help, Thor sought a team that could exhibit restraint and reserve. "I don't want a slab of beef who will slap someone around," he says. "I want intelligent guys who are reflective of my brand, and will barely get noticed unless they need to take action."

Contrary to action-movie imagery, many security specialists don't carry weapons, since local firearm laws vary and because the goal, of course, is to avoid an attack and move the client out of danger. In general, Fair says he advises other protection specialists to spend less time on the shooting range and more time practicing first-aid and driving techniques. If a principal is injured far from a hospital, medical knowledge can be crucial. And with many attacks aimed at vehicles, knowing how to execute a reverse 180 (Fair says anyone can master this with a little practice) or how to ram another car out of the way (aim your front headlights at the bad guy's rear tire) may mean the difference between a sitting-duck ambush and an escape. If things do get violent, having a can of pepper spray, or a martial art like Krav Maga, at your disposal can often prove more useful than a gun, particularly in tight quarters.

But perhaps the most overlooked executive-protection skill is not physical at all. It's social. The protector must develop trust with the protectee. "When I tell you to go left," says Fair, "and everyone else is telling you to go right, I need you to trust me."  

SURE ENOUGH, when my day with a detail arrives, I barely register Fair's presence most of the time. I often can't see him, as he's lurking just beyond the periphery of my vision. But he's got his eyes locked on me. And I begin to notice the little skills he's putting into play.

When we enter or exit my hired car, Fair has a particular choreography he employs. He opens my door from the side closer to the trunk instead of the hood, to ensure I'm never exposed to plain view. When a van pulls a three-point turn in front of us at an intersection, Fair instantly has us brake to leave evasive breathing room, while he simultaneously checks out the bus stop shelter at the adjacent curb to see if anyone there is eyeing us. Later, at the embassy party, he plucks a half-drunk glass of wine from a waiter's tray as a prop, so he can appear to be another reveler even though he never, ever drinks on duty. Every time we leave a venue, he's communicated with our driver in advance. The car waits just outside the door, as Fair scans the sidewalk for threats.

He's warm and friendly with my date—even when she blurts out in a lounge a few key details of our evening's itinerary, for any nearby bad guys to hear. He's always respectful and appropriate. And he has a knack for knowing when to blend into the scenery. I imagine it would be easy to forget he was with us, at times, even if he were trailing us for a week. I also felt assured that we could talk openly in front of him, with no secrets in danger of getting spilled.

More important—especially if there were a legitimate threat against me—I felt supreme peace of mind the entire time I had Fair watching my back. It's a calming, freeing feeling, and one I had never quite experienced before. And it's a difficult thing to put a price on.