In my previous apartment down at college where I lived for 3 years, there was this issue where everytime the neighbor in the room above mine would start to "get busy," if my door was closed, it would bang back and forth in the doorframe the ENTIRE TIME. There were a few times I took a broom like the guy in the cartoon here and knocked on the ceiling, as it was just too annoying some nights. And being garden level, if any of the neighbors upstairs had a party (which did happen on occasion, as this was a college town) all their smoker friends would tend to congregate at the bottom of the stairs, outside our front door and next to my window.

We first noticed last summer that it sounded like elephants were bowling or something upstairs, but we figured she must have gotten a bigger sized dog that ran around like dogs do.
I met her once, last September when Tiger went missing and I was walking around the premises looking for her. She was out on her balcony and started talking to me while I looked around for my kitty. She mentioned she has a big cat that lives with her, stating we've probably heard him, in which I said we had and she apologized for the noise. I figured maybe she'd make more of an effort to keep the noise down upstairs, but I was wrong.
Ever since it's only gotten worse.
Sometimes it sounds like people stomping around upstairs, sometimes I can hear her cat chasing a ball or something up in their alley kitchen - it must be one fat cat! Other times it sounds like she's moving heavy furniture around or bowling. And a lot of this we are hearing in the middle in the of the night!
I know, I know, don't live in garden level apartments - live on the top floor. Except I've found it's easier to move everything in and out when living on the lower level and you don't ever have to worry about people complaining about you. Plus, we have this huge oak desk my parents gave us and I think it would kill dear hubby if he had to carry it up and down stairs like that!
So I guess our only hope is to get a place of our own, which can't come soon enough!