Published Apr 16, 2026 | by Matthias Lenz
A black labrador retriever puppy in a blue assistance dog vest is leaning in, cautiously sniffing a video camera being held by a person out of the photo.

Raising Brave Dogs: Navigating Puppy Fear Periods

Many people who have recently had a puppy or work with dogs have heard of fear periods. While they are a normal occurrence, dogs from a successful assistance dog breeding program typically show milder reactions during fear periods compared to dogs that were bred for different purposes. This is likely because these breeding programs are producing dogs with stable temperaments, making it less likely for the dog to present with severe reactions during fear periods. If frequent, severe reactions during a dog’s fear period are common within an assistance dog program, the solution should be focused on the selection of breeding stock, rather than training and socialization of the individual dogs. 
While good breeding can reduce the frequency and intensity of fear periods, it won’t prevent them from occurring entirely. Remember, fear periods are a very normal part of puppy development. With well-bred dogs it could be the case that fear periods come and go without puppy raisers noticing the change in their dog. If a puppy raiser reports a sudden onset of fear to something that the dog previously encountered without concern, this is the approach I have found most helpful.
Firstly, determine if the trigger can be avoided either by avoidance or manipulating the environment. For example, for a slippery floor in the house, you can put towels down so the dog can move around the house without having to navigate the slippery floor;  if it’s a statue out front of a neighbour’s house, the dog can be lured around the house, or that direction can be avoided for some time.

It is best to avoid the trigger for 2-3 weeks before attempting to expose the dog to it again. During those weeks the dog’s brain further develops and the puppy has many different experiences that might be similar but unrelated to the trigger. Many times, when re-exposed to the exact same trigger a few weeks after the initial fearful reaction, the dog no longer reacts fearfully. If there is another fearful reaction to the same or a similar trigger within or after those 2-3 weeks , I suggest avoiding the trigger for another  2-3 weeks.  If the dog still shows continued concerns with the same trigger after 4-6 weeks of avoiding exposure, further assessment is recommended. Several dogs can be seen lying down in an open wagon being pulled by a horse.

The risk of trying to help the dog overcome things:

With many training techniques developed to help dogs overcome fearful reactions, why not use that knowledge to help these puppies overcome their fears during these periods? I have found a few reasons it is best to avoid this: 

  • When people try to desensitize their dogs to a certain trigger by repeatedly exposing them to it or using counter-conditioning protocols, they can often end up sensitizing the dog to the trigger instead, repeatedly affirming the dog’s fear response. 
  • When a dog is doing better than expected with the trigger compared to the past, it is tempting - not only for professionals but especially for volunteer puppy raisers - to try and push things a little further. Even with the best intentions, people can put too much pressure on their dog to get closer to the trigger, resulting in another negative reaction, thus ingraining the dog’s fear. 
  • If a dog has repeated negative experiences with a certain type of stimulus, they are  likely to have ongoing issues with said stimulus.
  • Dogs are more likely to imprint on their fear during fear periods.

Usually, it’s possible to avoid the triggers or reduce their intensity by creating a lot of distance. However, if the dog has a negative reaction to something that can’t be avoided at all, I suggest implementing a training protocol right away. In these cases, I find a classical counter-conditioning protocol like open bar/closed bar is best.

In summary, fear periods are a normal part of puppy development, with dogs from well-bred assistance dog programs often experiencing milder reactions due to their more stable temperaments. Rather than training through fear during these periods, handlers should focus on temporarily avoiding triggers and allowing the dog’s brain to mature as premature and poorly executed desensitization attempts can unintentionally worsen fear. 

 

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Matthias is smiling at the camera. He is holding a yellow labrador retriever puppy in his arms. Behind him is a house and yard.Matthias Lenz is the Director of Puppy Development at BC & Alberta Guide Dogs, where he leads the development and expansion of the organization’s puppy raising and early training initiatives. Deeply committed to collaboration and continuous improvement within the guide and assistance dog sector, he serves as Chair of the Webinar Committee for Assistance Dogs International and facilitates monthly networking meetings that connect organizations around the world. Matthias also contributes to the Ethics and Welfare Advisory Panel for both Assistance Dogs International and the International Guide Dog Federation, supporting high standards in dog welfare, ethics, and professional practice. He is also a co-host of an animal training podcast called 'Not Another Dog and Pony Show Podcast.' 

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