assign Key to midi clips?

Assuming you know what key it's originally in, you can highlight the clip and select Edit/Transpose.  Then raise/lower it the correct number of steps to match the new key.

thanks guys. i was having to do the "select clip" and "transpose clip" method.
wasn't aware of the transpose plugin, but then i'd never have thought to look for that, so thanks for the tip, bitflipper.

its no big deal- i recorded some "all midi" parts for student accompaniment tracks with increasing tempo, (easy done in midi from 70bpm - 170bpm) obviously no artefacts from time stretching "real audio" as this was just purely midi/soft-synths.
i had to do the same piece in a variety of keys and hoped i could click one option to move the key of the whole project. to have to highlight and transpose the various clips (except the drum part) is no major operation. i guess like the rest of us, if there is an easy or more efficient way to do these kind of tasks it gives us an extra few minutes to spend on these forums :P
thanks all

that sounds like what i was looking for. i must admit i never knew this existed having not needed it before. i'll give it a go asap. many thanks