How can I make my cell phone now work in a different country?

I am living in Central America. I need my cell phone to work in Paraguay. How can I do that? By the way, is it true that by just changing the sim card, and buying a new service it will work?How can I make my cell phone now work in a different country?
well depending on what service u have....u can get the unlock code from ur service provider...just tell them that ur gonna be going out of the country for a while and need to use ur phone but another sim card in order for u to make calls....thats pretty much all u have to do...i know u can do it with at%26amp;t and t-mobileHow can I make my cell phone now work in a different country?
It depends on your cell phone's feature and if it was locked. What you can do is ask a friend from another company to place their sim in your phone. If it works, then all you have to do is get another SIM card in paraguay.



What happens is, most phones are locked to one network but can be unlocked. These are GSM phones. And some phones are made specifically for a certain network and cannot be unlocked, these are CDMA phones.