Round One

The first round was usually a head-to-head competition played under a 60-second time limit. Usually, both dogs received points based on their performance, with the better-performing dog earning an additional ten points. For example, in one event, the dogs went down a line of doggy treats (on pie plates), and for each one eaten, they would get 2 points, with a 10-point bonus for the dog who could eat more of them faster. One notable exception was "Doggie Bag," in which the dogs and masters climbed into a large cloth bag and exchanged T-shirts; the team that first emerged from the bag within 60 seconds won 20 points.

During the show's first season, the round one competition was played for 20 points (10 if the race was half done).

Round Two

From then on, each dog played separately. In round 2, each dog had (usually) 30 seconds to perform a stunt for points. For instance, in one event, the dog had to bring slippers back to their master, picking up 5 points for each slipper brought back and 10 bonus points for each matching pair. Another event gave the dog 30 seconds to jump over a bunch of hurdles of varying heights, starting at one point for the lowest one, and six points for the highest. If a hurdle got knocked over, it was out of play.

Round Three (Mixed-Up Maze)

The third round was known variously as the Mixed-Up Maze, the "Twisting, Turning, Tricky Trail" and various other terms. Each dog had 45 seconds (60 in the final season) to get from the starting gate to their master at the finish line (who, true to the theme of the show, would be waiting in a doghouse structure during the final season). Along the way, the dog might be distracted by a sand trap filled with dog food, a toy car, a water bowl and other things. A dog making it through would earn 20 points, with the faster dog getting 10 bonus points (only applicable if both dogs completed the run). If a dog left the maze at any point other than the regular exit by either jumping over the outer wall or escaping through the giant mouse holes on the middle of each outer wall, that dog would be disqualified for the event and score no points for the run (and in the final season, a 'Runaway Dog!' graphic would pop up on the screen and sirens would go off). However, jumping within the maze structure was acceptable.

During the early episodes of the first season, the maze was played first.

Canine Quiz Round (First Season)

During the show's first season, the dog's masters played the "Canine Quiz Round". Host Skrovan asked a series of six dog-related questions and the first player to buzz-in (also called 'barking in') was given a chance to answer. An incorrect answer from the bark-in player allowed an opponent to answer. Each correct answer was worth 5 points. Later on in the first season, the sixth and final question of the round was worth a special prize from the Doggy Bag.

Round Four

The fourth round had two different formats:

Doggy Decathlon

The final round was the "Doggy Decathlon", an obstacle course. In the first season, the dog would have 60 seconds to complete 8 obstacles; in the second and third seasons, the number of obstacles was reduced to 7. In the final season, the dog would have 100 seconds to complete 10 obstacles. The course varied from week to week, but always (starting late 1992) ended with the dog leaping through the big letter "O" in the "That's My DOG" sign. Each completed obstacle earned 10 points; in the first season, a 20-point bonus was awarded if the dog completed all 8 obstacles within the time limit but during the second and third seasons, it was increased to a 30-point bonus if the dog completed all 7 obstacles before time ran out; in any case, a perfectly completed course would yield a total of 100 points. A dog could skip an obstacle, but jumping through the sign would always end the run, regardless of time remaining.

Winning

The team with the most points won the game. The winning family received prizes, while the winning dog won a year's supply of dog food (originally from Iams in the first season, later from Kibbles 'n' Bits for the last three seasons) and a gold medal. In some episodes where the final score was a tie, the dogs took turns wearing the medal; presumably, both dogs later received one. During the show's final season, there was a silver medal for the runner-up, and a gold one for the winner, both brought out by the show's resident dog Tiny.

Special Episodes

• Celebrity Dogs - celebrity dogs Rin Tin Tin (of Rin Tin Tin K-9 Cop) and Dryfuss (Bear from Empty Nest) competed, but they each came in with one master; they both played for charity.
• Christmas - in the fourth and final season, there was a Christmas themed show with appropriately themed events.
• Puppy Love - also in the final season of the show, there was a special Puppy Love episode aired where puppies did the events that adult dogs normally did. One of the puppies was actually only 10 days old (announced on the show), surprisingly enough. This turned out to be one of the lowest scoring games (before the Doggy Decathlon) in the history of the show, with both puppies struggling to reach double digits before the final event. It was likely the only time in the final season that both contestants failed to finish the decathlon before time expired (the closer one still had several obstacles to go when time ran out).