Leader to remain in touch to get commission (8)
I believe the answer is:
contract
'leader to remain' is the definition.
I can't tell whether this definition defines the answer.
'in touch to get commission' is the wordplay.
'in' means one lot of letters goes inside another.
'touch' becomes 'contact' (contact is a kind of touch).
'to get commission' becomes 'r' (I can't justify this - if you can you should give a lot more credence to this answer).
'contact' enclosing 'r' is 'CONTRACT'.
Can you help me to learn more?
(Other definitions for contract that I've seen before include "Document setting out terms of agreement" , "Promise" , "Come down with" , "settlement" , "Pick up" .)