Mexico - Top jobs in Mexican cartels -- such as money laundering and setting up smuggling routes -- are mostly reserved for relatives or close friends of bosses, but the gangs are often in the market for professional killers.
In one audacious move, the Gulf cartel openly advertised for army troops to desert and join it in April 2008, stringing banners from bridges over main roads in two towns near the U.S. border offering jobs. "The Zetas want you, soldier or former soldier. We offer a good salary, food and family care," the ads read.
The Zetas group itself began as an army special forces team that deserted to the Gulf gang in the mid-1990s for more pay.
Further down the chain of command, men at street corners with walkie-talkies in Rio Bravo receive about $400 a month as "spotters" to alert the cartel to military convoys in the area.
"What you see in Rio Bravo, you see all along the border. Cartel members are untouchable in the town. They can run operations and travel out to see their units," the source close to the Gulf cartel said.
The dirty work is often sub-contracted to third parties such as corrupt police officers.
Just before Christmas, soldiers found a list of dozens of police in Monterrey who received up to $1,500 a month to work as Zetas' backups and hitmen and to tip off the gang about any state security operations.
Drug gang wages are attractive to poorly paid police or Mexico's many unemployed, but one slip on the job can mean a gruesome death. Traffickers almost daily kill members who lose drugs or money, leak intelligence to authorities, switch to other gangs or try to wrestle away their turf.
In October, suspected hitmen from the Arellano Felix cartel in Tijuana hung the naked body of a local government official from a bridge, having first cut off his penis and tongue. Police say the official was likely working for the Arellano Felix clan and probably leaked information to the Sinaloa cartel, a rival for access to the Californian drug market.
Cartels force policemen, government officials and even doctors to work for them as a nationwide fight for control of smuggling routes tears at the fabric of Mexican society.
"You can't say no to these people. You take what they are offering or they kill you," said a doctor working for the Arellano Felix cartel in Tijuana who treats senior hitmen wounded in gunfights.
BLOODY SPIN OFF
In this world, boardroom battles are dangerous. Cartels retaliate violently to any challenges to their leadership, the army says.
In 2007, five brothers known as the Beltran Leyva family spun off from the Sinaloa cartel. In the ensuing power struggle, Beltran Leyva gunmen killed the son of Mexico's most-wanted drug lord, Sinaloa leader Joaquin "Shorty" Guzman, in 2008. Some 40 men fired more than 500 rounds at Edgar Guzman as he parked outside a shopping center in the city of Culiacan.
More so than its main rival the Gulf cartel, the Sinaloa gang in northwestern Mexico is a loosely run federation of allies who often act independently of each other. The alliance is probably the most successful cartel in the country. With a personal fortune estimated to be at least $1 billion, Guzman made Forbes Magazine's list of the world's richest people last year.
He is believed to live in the "Golden Triangle" of remote mountains in Sinaloa, Durango and Chihuahua state. A Mexican former attorney general described him to Reuters as being akin to a "chairman of the board." He leaves day to day business matters to the likes of operations chiefs such as smuggler Ismael Zambada.
In the United States, high-level Sinaloa distributors and dealers are required to live modest lives with false documents to avoid being traced back to cartel leaders, U.S. anti-drug officials say. They rarely have contact beyond their immediate superiors in the organization.
"The people moving the drugs don't know Guzman, they don't know Zambada, the cells are isolated," said Doug Coleman, the assistant special agent in charge of the Drug Enforcement Administration's Phoenix, Arizona division.
Mexican cartel franchises and distribution networks in the United States are outsourced, often to U.S. gangs in major cities such as Atlanta and Chicago, or to Mexican illegal immigrants in rural areas who are seeking to boost income.
When it comes to collecting the profits and getting them back to Mexico in large wads of cash, however, cartel relatives and direct employees are on hand.
Gangs and distributors take the proceeds from drug sales to networks of cartel cash collectors in U.S. cities who in turn use corrupt currency exchange businesses to swap small bank notes into $100 bills.
Trusted with up to $20 million hidden in a single vehicle, traffickers use spotters at the border crossings into Mexico to alert them by text messages when they think it is safe to get through. U.S. customs only sporadically check vehicles heading south due to a lack of manpower, although the U.S. government has pledged to step up its south-bound inspections.
Once in Mexico, the smugglers head to safe houses where, watched over at gunpoint, groups of mostly women and girls count the money by hand. The cartels wash their dirty money through businesses that can produce bogus receipts such as hotels and apartment buildings. The profits are kept in bank accounts in Mexico and abroad in places such as Panama, drug trade analysts say.
Despite the global economic slowdown, business is booming.
"Sometimes the cash is coming in so fast we can hardly deal with it," said a trafficker handling drug profits in a car junk yard in Tijuana. "We have hours and hours and sometimes days and days just counting money," he added.