i let DD walk in shopping centers as soon as she was able to walk. She would toddle along with me right behind her. I found it a great way to burn off some energy. Now at a little over 2 she walks a lot, we too have rules, she has to hold my hand and if she runs off she's straight into the carrier or pram. Initially she always wanted to go on the rides, but now she is great, asks me first and is mostly good when i say 'maybe later'. She is pretty good in shops when we go in a say "Now what's the rule?" She says "Look but no touch mummy" Again if she touches anything i pop her in the pram.

I guess with DD2 she wont have as much free reign because i will be splitting my attention between the two and wont be able to keep as much of an eye on her.

If we are shopping on strip shops or anywhere near cars she has to hold my hand or go in the pram/carrier.

I don't let her run wild but i do find it a good opportunity to let her have a little freedom and learn a bit about rules.