For individual coaching: Get someone to try their free hour and you get an additional free hour of individual coaching.
For enterprise coaching: Generate a lead that turns into a company giving me a trial day and I'll give your organization a free day of coaching.
This does not extend to clients for whom I'm working through an intermediary unless the intermediary agrees. In that case, check with the intermediary to see if they have a referral program or would like to agree to participate in mine.
As should always be the case, I reserve the right to decide that something is not being done above board at my sole discretion. I've heretofore never exercised that right.