The generation after Koehler saw a slow shift away from his style. "Like human therapies," write canine behavior experts Dr. Mary Burch and Jon Bailey in 1999's How Dogs Learn, "for the most part dog training has undergone an evolution and moved toward a more positive approach."
To a behaviorist, "positive" simply means a change of emphasis: Instead of correcting mistakes, the trainer focuses on rewarding good behavior, often with food. Mistakes are ignored. In the early 1980s, expatriate British veterinarian Ian Dunbar started advocating such then-unusual ideas as puppy socialization, off-leash training, and the lavish use of food rewards. Dunbar founded Sirius Dog Training in Berkeley, Calif., and later the Association of Pet Dog Trainers, to promulgate the new school of what he called "dog friendly dog training." Around this time, the clicker was popularized by dolphin expert Karen Pryor as a more precise way to tell the dog which behavior, exactly, you are rewarding.
Today, when you trot your dog into most training facilities in the United States, you will probably be taught using the so-called "click-and-treat" method. My own club, the Port Chester Obedience Training Club in White Plains, N.Y., is aggressively positive. It includes on its recommended reading list such feel-good classics as Andrea Arden's Dog-Friendly Dog Training and Joel Walton's Positive Puppy Training Works. And under a title by Paul Owens called The Dog Whisperer, they emphasize this is "NOT to be confused with the book with the same title written by Cesar Milan" (whom they hate too much even to spell his name right).
Millan doesn't use a clicker and rarely pulls out a treat. And he's openly contemptuous of what he sees as the overly touchy-feely bias of too many of his colleagues. In his 2007 book Be the Pack Leader, written with Melissa Jo Peltier, Millan complains: "We've gone from the old-fashioned authoritarian extreme—where animals existed only to do our bidding—to another unhealthy extreme—where animals are considered our equal partners in every area of our lives."
I would argue that Millan's tactics don't represent a full-bore regression so much as a renewed emphasis on the dog's status as inferior. While he does use leash corrections, Millan puts far more emphasis on what he calls "calm-assertive energy." His primary training tools are eye contact, aversive sounds like hisses, and even visualization techniques borrowed from sports psychology. In a laudatory 2006 profile in TheNew Yorker, Malcolm Gladwell compared Millan to a dancer.
Truth is, all these methods can work. Dogs are marvelously adaptive. There are many roads to the rainbow. Rewarding good behavior and punishing bad behavior both have the same end in view: more good behavior. For better or worse—in this generation and the next, no matter what the prevailing wisdom—dogs really do care what we think.
Correction, Dec. 30, 2010: Originally this article incorrectly referred to methods like the choke chain as negative reinforcement. In operant conditioning, the proper term is punishment. (Return to the corrected sentence.)