What small to medium sized dog breed is good with cats?

[Ocimom]

I'd rather answer what type of dog NOT to get Don't get any of the terrier breeds (except Boston Terriers). The worse one would be a Jack Russel or mix.

You don't want too small of a dog tho - maybe a mini poodle vs a toy. Other ones may be a spanial type. The important thing is either talk to the reputable breeder how the dog gets along with cats or the shelter. Shelters often do cat/kid testing before rehoming so you know if the dog is ok with both or the dog should not be placed with cats/kids.