Agree to keep frames of Monet and Rothko around in collection (10)
I believe the answer is:
assortment
'collection' is the definition.
(I know that assortment is a type of collection)
'agree to keep frames of monet' is the wordplay.
'agree to' becomes 'assent' (I've seen this before).
'keep' indicates putting letters inside.
'frames of monet' becomes 'ortm' (I can't justify this - if you can you should believe this answer much more).
'assent' going around 'ortm' is 'ASSORTMENT'.
'and rothko around in' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for assortment that I've seen before include "Medley" , "Variety" , "Miscellaneous collection" , "Miscellany" , "Mixture" .)