Related Clues:

• Reciprocally
• N. I. by way of repayment?
• Reciprocally N.I.?
• N.I. gives tit for tat
• As part of an exchange
• As compensation
• As a quid pro quo
• As reciprocation
• Driving instructor's memo opener?
• 'Measure for Measure' on-stage again?
• As payment (for) (2 words)