How do they install home security systems?

I am thinking of purchasing a home security system. I wondering if anyone knew how they install it. Do they have to go through your walls?

Any opinions on ADT Home security?

If it's a wired system, then yes they have to go through/behind the walls/floors/etc. It's much easier for them to do this if you have unfinished space (eg attic or unfinished basement). Most will sell you wireless systems as well, which of course is easier to install. ADT is one of the top "name brand" companies, but their prices reflect that. Lower priced local companies can provide the same or similar service at a much lower price.

there are wired and wireless alarm systems. if you are installing it yourself def. go with wireless. basically there is one control panel that serves as the actual sounding alarm and keypad. then you have door and window sensors, then a motion detector. go to http://www.homesecuritystore.com/ http://answers.yahoo.com/question/accuse_write?qid=20080102144611AAyL7Ff&kid=QJx5X2n7AkwTN9YYvANT&s=comm&date=2008-09-25+14%3A32%3A11&.crumb=

many are wireless...