Seeing a pet I worked really hard for get adopted by a person who loves them as much as I do. Also, seeing a person who thought their pet was lost forever reunited with them because of their microchip.
So many things! A few of my favorites: seeing a pet who's stressed out in the shelter get into foster and thrive, and seeing the amazing, more-successful-than-I-even-imagined-was-possible programs that our apprentices are creating.
Seeing all the success stories and learning how a new idea or practice addresses an old issue. We're so fortunate to have passionate, creative people in our field who won't stop until they find a solution. I love being a part of it and seeing more animals' lives saved because of it!