Ancillary K9, Denver's premier dog behavior expert, transforms challenging behaviors with personalized, intensive training. Our certified trainers address aggression, anxiety, and obedience issues. Clients see rapid, lasting results, often within six sessions. Our programs empower you and your dog for long-term success. With our Lifetime Training Assurance, we guarantee free retraining if your dog regresses. Offering private training and 24/7 support, we help rebuild harmonious relationships.
Training & services
Training goals
Behavior consultationProgram details
Expert training to address unwanted behaviors such as anxiety, reactivity, or aggression. We create customized plans to correct issues, build positive habits, and improve your dog's overall behavior, ensuring a happier and more balanced companion.
Comprehensive training designed to address complex behavioral issues such as anxiety, reactivity, and aggression. Tailored to your dog's unique needs, this program focuses on lasting solutions for a well-balanced and well-behaved companion.
Effective behavioral modification for dogs with anxiety, fear, reactivity, or other challenges. We address root causes and help dogs become confident and calm, providing solutions for behavioral problems with customized training in Denver.
Leash training
Obedience trainingProgram details
Professional dog obedience training to teach essential commands, improve manners, and build a solid foundation for behavior. Ideal for dogs of all ages, ensuring they are well-behaved at home and in public. Serving Denver and nearby areas.
Puppy trainingProgram details
Trusted puppy training in Denver to build confidence and teach basic commands. We guide your puppy through early learning stages for better behavior, social skills, and obedience. Perfect for new dog owners in the Denver area.
Socialization
Behavior support
Aggression trainingProgram details
Specialized training to address aggression toward people or other dogs. We identify root causes and use proven techniques to build trust, improve behavior, and ensure safety. Tailored for lasting results and a stronger bond with your dog.
Specialized aggressive dog behavior training to reduce reactivity and manage aggression. Our expert trainers help your dog overcome triggers and develop safer responses. Ideal for dogs showing aggression toward people or other dogs.
Fear and confidence
Reactivity trainingProgram details
Fast, effective reactive dog training in Denver for dogs that bark, lunge, growl, or struggle around other dogs and people. Practical training that gives you and your dog confidence and peace of mind.
Resource guarding
Separation anxiety
How training happens
Board and train
Group classes
Owner coachingCustomer-reported
Private trainingProgram details
One-on-one private dog training tailored to meet your dog's unique needs. Focus on obedience, behavioral issues, or aggression with customized sessions designed for faster results. Serving Denver with personalized, professional dog training solutions.
Dog age
Puppies
Support between sessions
Homework and practiceCustomer-reported
Personalized training plans
Assistance and working dogs
Protection trainingProgram details
Protection dog training in Denver focused on control, obedience, confidence, and reliable behavior. Training is tailored to the individual dog, owner, and their goals.
Dog size
Large dogsCustomer-reported
Your dog’s background
Rescue dogsProgram details
Dog training in Denver for rescue dogs adjusting to a new home or dealing with fear, anxiety, reactivity, or behavioral issues. We help build the bond between you and your dog.
Consultations
Free consultation
Other listed services
View 29 additional details
Dog trainingProgram details
Professional dog training to improve obedience, resolve behavioral issues, and reduce aggression. Tailored training programs for dogs of all ages and breeds, designed to achieve quick, lasting results. Serving Denver and nearby areas.
Aggressive Behaviors
Basic Commands
Behavioral Evaluations
Behavioral Program
Canine Rehabilitation
Court-ordered dog trainingProgram details
Court-ordered dog behavior training for legal compliance. Our training includes professional, detailed reports to meet court requirements. Available for Denver pet owners needing a thorough rebuilding of their dog's behavior.
Dog Behavior Assessments
Dog Bites
Dog Evaluations
Dog Park
Dog Starts
Dog Trainers Schedule
Dog behavioristProgram details
Dog behaviorist specializing in solving behavioral issues like anxiety, fear, aggression, and reactivity. We provide tailored, humane behavior solutions to help dogs thrive in any environment. Serving Denver and surrounding areas.
Dog's Barks
Dogs Treats
Family Dogs
Guard Dogs
Obstacle Courses
Off-leash dog trainingProgram details
Expert off-leash dog training to ensure your dog listens reliably, even without a leash. We focus on building recall, focus, and responsiveness, providing the freedom to explore while staying under control. Serving Denver and nearby areas.
Shelter Dog
Dog Temperament Assessment
Dog Temperament Test
Working Dog Training
Dog Anxiety TrainingProgram details
Trusted dog training for anxious. We work on building confidence, creating structure, and transforming your dog's behavior.
Seperation Anxiety Dog TrainingProgram details
Separation anxiety dog training in Denver for dogs that struggle when left alone. We’ll build a practical training plan to help your dog become confident and independent.
Destructive Dog TrainingProgram details
Dog training for destructive behaviors like chewing and damaging the home. We’ll help your dog building better habits, boundaries, and structure.
Dog Expert WitnessProgram details
Expert witness services for dog-related legal matters. Professional insight into canine behavior, temperament, aggression risk, and other issues in legal cases.
Dog Behavior Consulting for Legal MattersProgram details
Professional dog behavior consulting for legal matters. Experienced insight into canine behavior, aggression risk, evaluations, and other factors relevant to legal cases.
Confirm current programs and availability directly.
Questions & answers
From Google
What people have asked about this business.
Do you offer protection dog training?
Hi there! Yes, we offer Colorado's most trusted Protection Dog Training. We'll provide an assessment to ensure your dog is right for the role. Then we'll embark on a training journey that transforms your companion into a protection dog, and you into a strong handler. Please get in touch if you have more questions!
Community answer · Ancillary K9 Dog Training · 2025-12-21
Are there certain breeds that your dog training works best with?
Hi there! Though we have extensive knowledge and experience with Schutzhund and working breeds, our training is designed to work for any breed of dog. All breeds of dogs can have behavioral and aggression issues, and our training is equipped to tackle them all. If you have more questions, please get in touch!
Community answer · Ancillary K9 Dog Training · 2025-09-21
I'm struggling with a dog with serious behavior issues. Training in the past hasnt worked. Do you have any guarantees for your training?
Hi there! We specialize in hard to train or "problem dogs." Training is possible, even if other programs haven’t worked in the past. We are experts in dog behavior & obedience, and we guarantee fast, drastic changes in your dog. All of our programs come with Our Lifetime Support Guarantee, which is our promise to stand by you and your dog until your goals are achieved, as well as offering re-training if necessary.
Community answer · Ancillary K9 Dog Training · 2025-09-21
Do you offer puppy training? I have a puppy that's already starting to show some aggression and is proving hard to train.
Yes, we offer trusted puppy training. We correct your puppy's behavior fast, ensuring they have the best start at life. Correcting their behavior when they're young is the best way to see them grow to be a well-adjusted and happy adult dog. We'd love to help you tackle their behavior issues. Get in touch to get started!
Community answer · Ancillary K9 Dog Training · 2025-09-21
Private dog training offers tailored attention for specific behaviors and learning styles. It allows for flexible scheduling and results in faster progress. Our sessions are ideal for addressing unique issues, reducing distractions, ensuring a safe environment, and meeting individual goals. Owners receive immediate feedback and benefit from a private, relaxed setting, making it a preferred choice over group or board and train programs.
Community answer · Ancillary K9 Dog Training · 2023-09-21
In our training approach, we draw from the same methodologies used by law enforcement, military dog handlers, top sport dog trainers, and world-class competitors. Our methods are dynamic and are tailored to fit each unique situation. The tools and strategies we use hinge on the specific behaviors you want to address, your dog's individual temperament, and your proficiency and comfort as a handler. Our goal is effective, holistic training.
Community answer · Ancillary K9 Dog Training · 2023-09-21
Do you handle training for court-ordered behavioral assessments?
Yes, we are well-equipped to handle court-ordered dog training and behavioral assessments. We understand the seriousness and sensitivity of these cases. Our team is able to provide comprehensive evaluations and design tailored training programs to address specific behavioral concerns. We're here to assist and ensure that both you and your dog navigate this process effectively. Please reach out to us to discuss your needs and learn more about how we can help.
Community answer · Ancillary K9 Dog Training · 2023-09-21
Yes, we have extensive experienced in addressing canine aggression. Whether it's biting, growling, or other aggressive behaviors, we employ evidence-based techniques to manage and reduce these behaviors. We understand that aggression can stem from various underlying causes, and our approach is both compassionate and tailored to each dog's individual needs. Our goal is to ensure safety and foster healthy dog-owner relationships.
Community answer · Ancillary K9 Dog Training · 2023-09-21
Yes, we absolutely offer puppy training! Starting early is key to a well-behaved adult dog. We recommend starting training for puppies once they reach 16 weeks of age and have been fully vaccinated against parvovirus. This ensures their safety while they embark on their training journey. Our puppy programs are tailored to the unique needs of young dogs, laying a strong foundation for future training. For a comprehensive overview, please visit our website.
Community answer · Ancillary K9 Dog Training · 2023-09-21
While our primary base is in the heart of Denver, our reputation has traveled well beyond city limits. In fact, we've had the privilege of working with passionate dog owners from as far as Vail and Aspen. This expansive reach underscores our commitment to excellence and the trust clients place in our services. Regardless of distance, we remain dedicated to providing premier dog training to help build stronger bonds between owners and their dogs.
Community answer · Ancillary K9 Dog Training · 2023-09-21
At the heart of our service, client success is paramount. We employ a diverse range of techniques and tools, ensuring each client benefits from the most effective and tailored training. Recognizing that questions and challenges arise, we provide unlimited phone, text, and email support between lessons, ensuring continuity in your dog's progress. Moreover, our commitment to you is unwavering, backed by our Lifetime Support Guarantee.
Community answer · Ancillary K9 Dog Training · 2023-09-21
We do not! We believe in providing holistic support throughout your training journey. Not only do we NOT charge for assistance between lessons, but we also prioritize open communication. To encourage this, we give all our clients direct access to their trainer's personal contact details. This ensures 24/7 availability for phone, text, and email support. We're committed to standing by you every step of the way.
Community answer · Ancillary K9 Dog Training · 2023-09-21
What is your policy if I am not happy with the training?
We operate on a mutual commitment principle. If you're fully engaged—attending sessions, asking questions, and completing homework—we'll match your dedication. Your input reflects the support you receive. While we're eager to help, progress requires joint effort. If you're fully committed, we'll stand by you and your dog until you achieve the goals you're aiming for.
Community answer · Ancillary K9 Dog Training · 2023-09-21
5/5We found Ancillary K9 Dog Training when we were feeling pretty helpless about the dynamics between our dogs. Ludo had been reactive to other dogs in the past (and we had done prior training with other groups and personal trainers) and then things progressed and he started becomin…Read full reviewClose full review
We found Ancillary K9 Dog Training when we were feeling pretty helpless about the dynamics between our dogs. Ludo had been reactive to other dogs in the past (and we had done prior training with other groups and personal trainers) and then things progressed and he started becoming aggressive with our two other dogs in the home. Everyone (dogs and humans) were on edge all the time and we were exhausted trying to keep everyone safe and happy. We are so incredibly grateful to have come into contact with Dion at Ancillary K9 Dog Training, as I’m not sure Ludo would still be in our home if it weren’t for his training and guidance. Ludo went to the vet for the first time since his training and his vet said this was the best he had ever seen Ludo, which brought tears to my eyes. It is hard work, but if you put in the work you will see the results. We have noticed Ludo is much more calm in all aspects of his life, and still a very happy boy, despite more “rules”. Our other two dogs also finally seem comfortable in their home because of these changes. I am forever grateful for the guidance we have received from Dion. He helps train your dog, but also trains you by giving you the tools you need and the confidence to use them.
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Jack Egan
5/5This training has helped my pup, Joey, act and behave like a different dog. Along with that, this training has allowed me to feel like I understand how to work with my dog in a way in which he understands me. I had done previous trainings and always felt like I was left lacking t…Read full reviewClose full review
This training has helped my pup, Joey, act and behave like a different dog. Along with that, this training has allowed me to feel like I understand how to work with my dog in a way in which he understands me. I had done previous trainings and always felt like I was left lacking the skills needed to do at home training. Dion is always readily available, fantastic at what he does, and was always flexible with my schedule. I highly recommend Ancillary K9 to anyone who wants their dog to achieve an exceptional level of training. Thank you Ancillary K9!
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Thomas Wilson
5/5Dion has been a fantastic trainer. After trying different classes and trainers over the years, we were left feeling quite frustrated with our lack of progress with our german shepard. Despite putting in time and effort in various classes, our shepard was still reactive and had ba…Read full reviewClose full review
Dion has been a fantastic trainer. After trying different classes and trainers over the years, we were left feeling quite frustrated with our lack of progress with our german shepard. Despite putting in time and effort in various classes, our shepard was still reactive and had basic obedience issues. Ultimately, we started avoiding certain parks and situations because our shepard would become too hard to handle. I do not miss those days.
After just a few sessions with Dion, his training stuck and we were seeing progression daily. Where he really excels is in changing your attitude and mindset towards training. In my opinion... this is where the change comes from.
We now have a transformed dog and the freedom to take him places without stress or worry. Training with Dion has been an absolute pleasure, our dog is an integral part of the family and we can't thank him enough for what he's done for us.
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Luis JeGa
5/5I made the decision to go with Ancillary K9 because I got a puppy that was incredibly dog reactive. After a couple months of throwing treats on the ground trying to distract my pup as other trainers teach, I got desperate and am so happy that I came here. My relationship with my …Read full reviewClose full review
I made the decision to go with Ancillary K9 because I got a puppy that was incredibly dog reactive. After a couple months of throwing treats on the ground trying to distract my pup as other trainers teach, I got desperate and am so happy that I came here. My relationship with my dog is 100% better as she is no longer the wild puppy she was before I started.
Dion is an incredible dog trainer and great teacher. He lays out exactly what you need to do and how to do it in an effective manner, and you will see serious results after just a couple of sessions.
I constantly get praised with how well behaved my girl is, and am confident taking her to busy parks with dogs everywhere. If you’re considering here or a board and train, this is a great less expensive option. Plus side is you can take the lessons you learn and apply them to other dogs you may have later on in life.
For any energetic, working line dog that is out of control, do yourself a favor and go with Ancillary K9, you won’t regret it. The team is helpful, responsive, friendly and accommodating if anything may come up.
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Henry M
5/5Amazing trainer! Dion is super easy to work with and makes sure you have everything you need to successfully train a dog. I’ve been working with my 9month old puppy and her behavior has improved dramatically in the course of only a couple of months. I am constantly getting praise…Read full reviewClose full review
Amazing trainer! Dion is super easy to work with and makes sure you have everything you need to successfully train a dog. I’ve been working with my 9month old puppy and her behavior has improved dramatically in the course of only a couple of months. I am constantly getting praise at how well behaved and calm she is…and walks on leash like an expert! Dion always makes sure you ask any questions and is available anytime over text or call if something comes up. There is no magic switch to training a dog, but Dion will train YOU so you can train your pup properly. There is hand-on work required between sessions but you will bond more with your dog and be able to have confidence with your pup. Thanks Dion!
Original customer experiences from the collected Google data. Ratings without comments follow written reviews.
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