Created for the Argentina Foundation For Liver Transplants, a moving one-and-a-half minute long video clip has now gone viral, notching up more than 2.5m views in just five days.
It depicts an older man and his loyal, canine companion who never leaves his side.
And when his owner is rushed to hospital, the hound dutifully follows, waiting for days outside as dozens of patients, visitors, and medical staff come and go.
He only responds when a young woman is wheeled out – evidently having benefited from an organ transplant: the dog's elderly master may be dead, but he lives on because of his commitment to organ donation.
Twitter was quick to respond, with one user stating: "I just watched this again. Can't deal – Rip your own heart out watching this loyal dog in this organ donation ad."
Another said: Heartbreaking organ donation ad shows that a dog's loyalty Never ends." A third stated simply: "A different take on promoting organ donation. Beautiful ad."
In Ireland, you can request an organ donation card here.