All Montreal English hospitals are run by the MUHC (McGill University Health Center) and through volunteering I have signed the organization's joint confidentiality agreement. Therefore shadowing hasn't been an issue. I even managed to shadow a family doctor in his private practice - he was a friend of one of the docs at my hospital. I did Shad Valley McMaster, much of the program was medicine/hospital related, so we all had to sign a CA at McMaster General/Children's. Through that I managed to shadow the doc at McMaster.
So I've shadowed 2 docs I met volunteering, 1 (at McMaster Children's) who was the daughter of my 11th grade chem teacher (all three offered), 1 from a girl I used to mentor, I helped her through a hard time, had no idea her dad was a doc until she told her dad I was premed and he offered to allow me to shadow him for helping his daughter (one of the wonderful ways kindness could yield unexpected rewards), and 1 from the premed society's shadowing program. If you're friendly and kind to everyone, opportunities will fall in your lap (if you are a volunteer with a good reputation who has signed a confidentiality agreement with the hospital/consortium). One of the things i have learned through the years is to always keep your heart open. You would never believe the kind of rewards you get from it, not only the satisfaction of making people's lives brighter because of your existence, but also people who are excited to do nice things for you because they feel you deserve it. I consider myself extremely lucky, however.
I don't want to turn this into a Dalai Lama speech, so I'm going to end here.