It's definitely ok to contact t between sessions if he's said that you can. I think most t's know their limits and would only offer out of session contact if they felt they could handle it. I know some t's say no contact between sessions which to me seems a little harsh but if it would be too much for them to have that extra contact I suppose it's better that they state this upfront. My t has said I can call and e-mail between sessions but she didn't give me any rules about this so I've made up my own - can call between 9-5 monday to friday (though I've never called apart from cancelling sessions), e-mails anytime monday to friday but not from 6pm friday to midnight sunday. And only one call or e-mail a week. My t doesn't know about these 'rules' though. I think I like having my own rules rather than her imposing them on me. Then I'm not worried about getting in trouble if I break the rules seeing as they're my rules anyway. I think if you called or e-mailed a lot it might be a problem but I don't think once or maybe twice a week is too much especially when you're dealing with difficult stuff.