It is important that you feel secure in the knowledge that discussions with the coach remain confidential. The coach will provide you with an assurance on confidentiality.
For example:
"Information of a confidential nature may be relayed during the coaching sessions. I will not, at any time, use or disclose this information to anyone else without the specific approval of the coachee (excluding disclosure of illegal or unethical activities). I will explicitly obtain approval from the coachee to share information about the coaching with an appropriately qualified coaching supervisor."