I have brought my keeshond (see userpic) on the bus/train on a weekend day, and had no issues. However, the bus got a little crowded and someone with a wheelchair had to come on, necessitating me to pick up my pooch and sit him on my lap (he's about 40+ pounds, but likes my lap). Luckily, we had a seat facing the aisle, so that worked out well for him and I. But he's very calm and good at ignoring people/other critters if I tell him to.