Ideally, operating a book should be fairly simple. The bookies intent is to balance the amount wagered on both sides equally. That way, he collects $11 from the losing side, pays $10 of that to the winning side, keeps the $1 vig as his profit, and has none of his own money at risk. Of course, it doesn't always go that smoothly. But that's where moving the line and laying off to other books comes in.

Philadelphia mob turncoat George Freselone gives some great insight into the business in his book "Blood Oath." He ran a very profitable sports betting operation for the Bruno family in North Jersey. But his partner, without him knowing it, would sometimes fail to lay enough off and they'd lose money in the short run. He said that didn't bother him so much because they could make that up within a few weeks. But it was getting the money in the meantime to pay the winners. So he had to borrow from a loanshark in his own family.

Freselone also said that, while a bookie will send the leg breakers out on occasion, especially if the bookie thinks a player is trying to cheat him, no amount of beatings are going to get the money from a guy who simply does not have it. And if the bookie leans too hard, he might cause the debtor to run to the cops. So he said it really is an art of getting players to lose and pay up willingly.

Some bookies also double as loansharks. Others will simply refer a debtor to a loanshark. And, as shown above, some bookies go to the loansharks themselves if they need to. Loansharking is also an art form because the same thing applies about not leaning too hard, dead guys not paying up, etc. That's where the mob has become very enterprising, i.e. bleeding a guy's business via a bust out, getting a tip on a score, or whatever.