There have been studies that show that pet-friendly workplaces tend to have more productive work environments, lower levels of stress and anxiety, improve overall emotional and physical health, lead to decreased absenteeism, and appear to boost morale and improve work-life balance.

The Human Animal Bond Research Institute (HABRI) includes fun videos about pets in the workplace called The Woofice as well as a handbook on how to create a pet-friendly environment: The Woofice | HABRI
 

That being said, any dog allowed in the workplace, including those who are service animals, should be well-behaved and not cause disruptions in the work environment. Employers who are promoting a pet-friendly work environment should have guidelines in place for allowing dogs in the workplace which may include requirements for supervision, vaccinations, adequate training, and a “no barking” policy as well as employee responsibilities for damage, cleaning, disruptions, etc.
 

Additionally, there should be an option for employees that have allergies or do not like dogs to have an alternate “pet-free” workspace.
 

As for what you can do to improve the situation if your supervisor isn’t addressing the issue – contact Human Resources. Let them know about your concerns, the dog’s behavior, and the actions you’ve taken to address the situation with your co-worker and supervisor. HR should take the next steps to speak with the employee who has the dog and remind them of the guidelines for animals in the workplace; HR should also speak with the supervisor to let them know how the situation should be handled in the future.