Which of the world's 300 dog breeds takes the top spot when it comes to the wag-tailed workforce? From truffle hunters and bedbug detectors to emotional support dogs and penguin protectors, follow these four-legged experts at work.

At Ronald McDonald House, Gus helps youngsters by sharing a few cuddles. Tui's gift for defining different scents keeps her close to her owner Emily.

Maya's OCD makes her a superstar in the canine world. Telly and Billie both play big roles in helping to deliver therapy and counselling.

From providing friendship in a retirement village to being responsible in a search and rescue team and coaching the Australian national rowing team, meet the dogs who know when it's time to put their best paw forward.

In Auckland, New Zealand, giant schnauzer cross Monty has been trained to drive.

At Australia's Werribee Open Range Zoo a special squad of guardian dogs is being trained to help protect endangered bandicoots.