A sticky work situation?

I work in a "work group" with another girl in my office- we share responsibility for about 15 phone lines, and we're not supposed to leave our desks at the same time if we can help it.
She shows up late to work almost every day. This didn't initially bother me, because I liked her as a person and we got along well in most other capacities.
Recently though, she's started showing up even later (around 30 min. every day). Now it's affecting my job performance because I have to wait for her to show up before I can leave my desk. Often that means sitting around doing nothing for half an hour or more. Also, I'm starting to feel like I'm being taken advantage of (we're paid by the hour and I know she's not deducting that 30 min!)
She's been with the company a lot longer than I have so I'm not sure how to approach this! I don't think she'd be receptive to criticism from me, but I'm also worried about ruining our good rapport if I go over her head to our supervisors. Help please!

Why hasn't management noticed? WHat I would suggest you do is when you are next stuck at your desk because she is late....and make sure shes like 20 minutes late....call a superior and say "I'm so sorry but I havent been well and I really need to go to the bathroom but X isn't here yet...can you cover please?"
Then they will see that she is late but you havent tattled....repeat the operation as often as possible.

If you do not have the tact it takes to gently tell her she really should start making an effort to get to work on time, then don't say anything. It is terrible torture to feel uncomfortable with someone you work close with. I know. I have had to do it, and I really liked my job, and did not have the option to seek another job. Nor did I want to leave. So maybe if you can give her kind little hints, and she does not respond, just suck it up and deal with it. It would be better than the bad feeling you will get if she gets mad at you.

First of all, this is a fault of your supervisor. You should be having this problem. Now, given that you do anyway, are you the only one being affected? If so, then you're stuck - you'll have to either eat it indefinitely or else go to your supervisor or THEIR supervisor, hopefully in confidence. If others are being affected too, then maybe get a few of them to come with?

Ultimately, you should probably do something or it will just go on and on and it's not right.

Tell your boss you have a doctors apt befor work and will be late probably 15 to 30 mins..dont tell your co worker just let her be late and let the boss find out on his own

Moby, I have been where you are on my past job and I ended up finding another job. I spoke to this guy about being late and on some days doing his paperwork or reports. I got tired of it and I was worried about talking to him because he had been on the job longer than me and the boss really liked him. I decided to talk to him one day after work. I told him in a very polite way that I wasn't going to cover for him anymore and that I felt that all he was doing was using me to do his paperwork and reports. I told him that if I can be to work on time everyday and do my work then I felt that he could do the same. He got very upset with me and told me that he didn't ask for me help to begin with and that he was offened by my words. He walked away very upset. The next day I got a note asking me to come to the bosses office when I got there this guy was there as well and he had told our boss that he was covering for me and doing me work. I was stunned but I told the truth about the matter and I had the proof. Always keep a record no matter what thats your proof. I found a better job with higer pay and the guy well he was fired but I heard that the company hired him back. Losses for them. Don't let her get away with using you. You aren't a rug that she can walk all over unless thats what you want her to do. She can't do anymore than you let her. So what if the two of you aren't friends anymore. She isn't a good friend from what I'veread anyway. She will get over it and if she doesn't then thats her losses. God doesn't want you to be a fool!

If you don't speak up the problem will continue and could even get worse. When people take notice that they can take advantage of you they for sure will continue on doing so unless you speak up for yourself.