I agree that you have to be VERY careful with Yorkies (or any small breed) in a pool, but mine love to swim. They especially like getting on a raft and floating around in the water with me.
Here are two of mine and my mom's Yorkie and her Shih Tzu mix in the pool on our Florida vacation last year. They all loved to run around the edges of the pool and chase each other, and my little one DeDe slipped and fell in the pool at one point. Even though she had been swimming earlier and does it well, she panicked and was frantically turning circles because the fall shocked her and she was far away from the steps. I was right there to grab her though within 10 seconds, but I can only imagine what might have happened if I hadn't been there. I also have a pond in my backyard and when they're outside playing a couple of them like to try and sneak in. I NEVER let mine around water without being right there with them...heck I don't even let mine outside period without me right with them. Yorkies have that terrier personality in them tucked away, so if they can get into it...they will! I don't trust mine at all...
