The significance of interdog sociability is grossly underappreciated until one finds himself living with a dog that appears hostile toward members of its own species. Jean Donaldson's Fight! addresses the tricky problem of interdog aggression and its remediation.

Written for the dog trainer or well-read dog owner, Fight! "is about dogs who fight with, lunge at and don't get along with other dogs." Donaldson functionally classifies interdog aggression into six categories based on the treatment approach best suited to correcting each.

Tarzans, as the name implies, are starved for interspecies social contact and have the kind of boorish social skills that lead them to hurl themselves at other dogs and start fighting at initial contact. Dogs with play skills deficits, by contrast, are able to greet and play but tend to get carried away and begin fighting as things overheat. Bullies are similar, except that they tend to single out specific dogs to torment, while playing appropriately with others. On the other hand, proximity sensitive dogs would prefer to avoid social contact altogether and may reactively or proactively aggress to maintain social distance. Resource guarders aggressively defend food, toys, locations, or people from other dogs. Lastly, compulsive fighters don't appear to engage in normal social behavior and have a genetic predisposition to fight. Not surprisingly, dogs may present with multiple types of interdog aggression, and classification may be confirmed or disproven as one observes the dog's response to treatment.

Donaldson's writing is intelligent, straightforward, and presumes a working knowledge of behaviorist terminology. From the outset, she rejects the temptation to buy into anything other than a behaviorist approach to the topic. Her observations about the current understanding of canine dominance hierarchies are pithy and amusing, as she highlights how little is certain, despite various assertions to the contrary. Donaldson's point is well taken that "a disciplined focus on what the dog is doing (or not doing) is usually more fruitful" than speculating on the dog's thoughts and motivations.

Donaldson outlines strategies for reforming dog-aggressive dogs, with an emphasis on teaching appropriate social skills through actual social encounters. Her exceptions are compulsive fighters and dogs with poor bite inhibition. She sensibly asserts that these animals should be managed on-leash or always muzzled around other dogs for safety, as "the risk of a bite both during and post rehabilitation is huge." However, for many dogs, she doesn't focus on merely training them to ignore other dogs on leash, but to tolerate or enjoy play groups and dog parks. This can be the quality that makes the book most useful, or most irrelevant, depending on the reader's values and goals.

Treatment for a "Tarzan," for example, might involve both carefully orchestrated play sessions with other dogs, as well as teaching leash manners and on-leash greetings. For the typical pet owner whose goal is merely to walk around the block without aggressive eruptions, this approach to treatment might feel like overkill, even if it is effective.

Donaldson's approach does have its limitations, among them that it often requires the cooperation of several other, well-socialized dogs and their owners. It may not be the answer to all readers' concerns. The relatively common scenario where a dog explodes into redirected fighting during high arousal situations is not specifically addressed, for example.

Nonetheless, this is a useful little book that contains plenty of good information. Its limited scope and targeted brevity render it a palatable and handy reference. This is a particularly valuable book for anyone who frequents dog parks or other play groups, as it may help the reader to recognize and deal with budding issues before they become more serious problems.