### Clue: Vital for credit union agents to be online (7)
### Answer: CRUCIAL 
 ### Explanation: Definition: Vital
 CR(abbrev. for "credit", in a bank statement, say) + U(abbrev. for "union") + CIA(abbrev. for the US Central Intelligence Agency, of secret agents, that is) **placed above**(to be on, in a down clue) L(abbrev. for "line").