How to address someone in a job-related email (Mr/Ms)

This might be a pretty stupid question but it’s something I’ve been having a lot trouble with.
I’m getting prepared to get my first internship and have been sending lots of emails.
When you communicate with someone through emails, what’s the proper way to address the person you’re talking to?

I’m not sure how long I have to stick to “Dear Ms or Mr (last name),”
Or when it’s okay to just say “Hi (first name),”
Specially, I don’t know what to do when they respond by signing with their full name…
So confused…
I don’t want to sound rude or too polite I guess.
I appreciate your help in advance.

Thanks,
Alex

I think Hi (first name), is fine.
If they don’t know you, introduce yourself and maybe let them know who you got their info from.

I wouldn’t over think it, as long as you’re polite and use proper grammar (very important, maybe have someone read over it if you’re English is not that good) you should be fine.

I would write Dear … if I was writing a cover letter, but it’s always seemed too formal for an email to me.

While there are many subtleties to interpersonal communication, I find it’s always best to err on the side of being over polite. People are rarely offended at politeness. And if they correct you by saying “Please, call me Steve”, then you are free to call them by their first name.

For other info this is a good place to start: http://www.emilypost.com/communication-and-technology

On that tip, I prefer Hello, or just the name ie “Michael,” or “Mr DiTullo”

Hi implies you know me… beyond the forums…

Mr is fine.

All this goes out the door if the work is really good…

Yeah, “Hi” is kind of like waving, “Hello” is more handshake. Good Morning/Afternoon is perfectly fine though.

If the work is truly stellar I might give a pass on the introductory formalities, but then, the designers that we look for will spend a lot of face time with clients, many of whom expect respectful correspondence when initiating contact.

I often use their full name and that is it. I do this when i do not know them and am unsure if they are male or female.

Great advice. That can get very embarrassing.