The paperwork, recovered by Mexican authorities from a suspected associate of the drug don, Joaquin Guzman, show that he has a sophisticated counterintelligence operation and is a master at buying off top police officers and soldiers with his ample drug profits.

The documents, leaked to Mexico’s Reforma newspaper, were recovered from a Hummer last year that the authorities said belonged to Roberto Beltran Burgos, a suspected lieutenant of Mr. Guzman. The papers, including some internal government documents and ledgers written in code, strongly indicate that Mr. Guzman — who goes by the name “El Chapo,” or “Shorty” in Spanish — knows about the deployment of law enforcement officials beforehand, has the cell phone numbers and email address of many of those pursuing him and regularly pays off people on the inside.

Mr. Guzman makes heavy use of land routes to get cocaine, marijuana and other drugs to the United States, but court records also revealed by Reforma indicate that he is exploiting Mexico’s long Atlantic and Pacific coastlines as well, with confederates working at numerous strategic ports.

“As these documents show, it’s clear that he has informants at various levels of law enforcement,” said Malcolm Beith, a journalist who has a forthcoming book on the hunt for Mr. Guzman called “The Last Narco.” “Obviously, he has information leaked to him before any raid. He has so many levels of protection.”

Despite President Felipe Calderón’s aggressive anti-drug offensive, Mr. Guzman’s Sinaloa Cartel continues to dominate the market, and much of its top leadership remains intact. That has led to suggestions by some critics that the government has gone easy on Mr. Guzman’s operation, an accusation Mr. Calderón forcefully denies.

“It’s absolutely false,” the president told reporters in February. “I can state clearly that the government has attacked without favor all criminal groups in Mexico without taking into consideration whether it is the cartel of so-and-so or what’s-his-name. We’ve fought them all.”

As evidence, Mr. Calderón points to members of Mr. Guzman’s operation who have been killed or captured, including Vicente Zambada, the son of one of the cartel’s top leaders who was recently extradited to the United States. But critics point out that of the tens of thousands of arrests over the last three years, other cartels have suffered far more detentions than the traffickers in Sinaloa.

Some of those involved in the hunt for Mr. Guzman say it is not a lack of effort that has stymied their efforts. Rather, his infiltration of communities is so extensive that even when surprised he can find a way to escape. And the documents indicate that he is not surprised all that often.

Mr. Guzman does not give interviews, although one of his fellow leaders of the Sinaloa cartel, Ismael “El Mayo” Zambada recently spoke to Proceso, a Mexico news magazine. Julio Scherer Garcia, its editor, described a series of cloak-and-dagger interactions with middlemen that eventually led him to a mountain hideaway, where Mr. Zambada awaited him.

“The problem with the drug business is that it involves millions,” Mr. Zambada was quoted as saying. “How do you beat that? As for the bosses, jailed, dead or extradited, their replacements are standing by.”