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Service Dog Training Institute


What General Characteristics to Look for in A Suitable Adult Service Dog Candidate

Dog confidently crossing a busy street beside handler

Selecting Adult Service Dog Candidates

Whether a dog will be an acceptable assistance dog in public over the long term is dependent on many varying factors.

Since there is no consistent definition of ‘success’ for either owner-trained or program-trained assistance dogs, any statistics are general indicators at best. Success rates for shelter dogs becoming Assistance Dogs is between 5%-15% for one program.  Program-trained Hearing Alert Dogs from shelters from one facility had up to up to 31.5% success rate. Hearing dogs need to be more active and alert and a wider variety of breeds were typically accepted. The best success rates for the hearing dogs came from mixed and purebred lap dogs (companion breeds), spaniels, and terriers.

Comparatively, specifically bred guide dog puppies had a success rate between 50% and 80% for some programs. 

There are no statistics available for success rates of owner-trained assistance dogs. We do know though that many owner-trainers have multiple dogs since several prospects have been removed from training or service in their prime due to health or temperament issues. Sources of their dogs are both from breeders (of varying reputation) and shelters/rescues. 

If starting with an adult dog sounds like a better option for you in your situation, there are some foundation desirable characteristics to look for and others to avoid in adult dogs. Since shelter and rescue dogs have unknown health histories, have serious candidates X-rayed for hips, elbows and do other health tests typical for the breeds to rule out those types of problems before accepting the dog as a candidate. These tests may be done when you have them reproductively altered, typically around 2 years of age.

Here is an article that will be of interest that compares data for purebred with mixed breed dogs. 

Desirable Characteristics of a Service Dog Candidate

These are the key characteristics for an adult service dog to have.

Once a dog is an adult, about 18-24 months old,  the temperament is pretty much set. While behaviours can be changed, the temperament drives the underlying response to situations. Adolescent dogs (6 mos to 17 mos) with an unknown social and environmental background are hard to tell what they are and what they may become. They may be in the middle of a fear period or may not. Additionally, transitioning homes during fear periods is very hard on most dogs and can affect the development of their temperament. That is why we want to consider only dogs that are 18 months to 3 yrs. In general, dogs under 3 years old will be able to provide a duration of service that is reasonable for the amount of training that needs to go into a dog to become a service dog. In some cases, you may consider dogs unto 5 years of age. More on that below.

  • adaptable to many different situations and expectations
  • confident-has low level of stress as the job as a service dog can be stressful
  • optimistic attitude-is persistent to try again even when what she tried didn’t work the first few times
  • friendly and approachable-with kids (not just tolerant as you never know when a child might run up and fling her arms around the dog), adults, men, seniors but not overly friendly as you need the dog’s focus to be on you
  • dog who is good at social interactions in general
  • polite, dog asks before doing a behaviour rather than just pushes way into it
  • good body awareness for where her body is in space (not knocking into things, people) called proprioception
  • be food or toy motivated or both for training
  • wants to interact and be with people
  • low to medium exercise needs (unless you lead an active lifestyle)
  • forgiving if you accidentally run over his feet with a wheel, bump into him while walking, or an ear, foot, or flank gets pinched or squeezed
  • resilient- bounces back quickly after a scare or correction, quickly meaning a few seconds
  • social with other dogs (polite but not overly interested)
  • good with cats and other animals as they are found in many public locations
  • low to no prey drive easy to live with
  • inhibited bite when in play-a soft mouth is ideal
  • tolerant to loud sounds like thunderstorms, gunshot, fireworks (must have been introduced when young)

Additional skills

loose leash walking is a bonus as it can be a long haul to retrain this in some dogs


Rule out health issues:

  • joints: knees and elbow, hips
  • eyes
  • deafness
  • severe allergies
  • bowel issues
  • bladder incontinence or withholding urine
  • chronic ear infections, skin issues

Unacceptable Characteristics of a Service Dog Candidate

  • moderate to severe behavioural issues (you do not want to take on a rehabilitation project)
  • fearful, shy dog that startles/snaps when woken up or growls when disturbed when resting
  • aggressive/territorial/protective (is wary or stiffens when strangers approach handler)
  • dog that do not tolerate people in their personal space
  • overly social-jumping excessively, over-excited
  • high prey drive for cats, small animals, birds, small dogs
  • dog that takes a while to recover from incidents (not forgiving of toes being stepped on etc)
  • over-reactive to such situations
  • fearful/very uncomfortable around children
  • reactive (pays much more attention than is normal or suitable for the situation to sounds, sights, smells, movements of people, other dogs, bikes, cars etc) These dogs often scan the environment constantly
  • dog that barks often (whether excitement, protection etc)
  • noise/sound sensitive (electronic sounds, loud booms, thunderstorms) -be wary of dogs that have been on e-fence system as they have a high chance of being afraid of electronic sounds.
  • nervous dog
  • uninhibited bite during play, unaware of where mouth is or own strength
  • dogs with poor work ethic-want a dog eager to do something for us
  • low interest in training
  • personality conflict with handler for example dog enjoys physical contact and the handler does not
  • too active for handler’s lifestyle
  • too intelligent for handler to live with
  • is a wolf or coyote mix

Wondering how to train your own service dog?

Check out our Service Dog Training Institute classes (for both human and dog).
If you want to learn how to train a service dog like a professional, these classes will give you the skills to do so and to train other pet dogs! You learn as your dog learns.

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