Asking someone you do not know to mentor you

Example of writing to an unknown contact (a referral, someone you have not spoken with or written to in the past):

Dear Susan,

My name is Jane Doe and I currently work for Yale University in the Development department. I’m new to this field, and have great respect for the work you have done, particularly in grassroots fundraising. I would like to hear your career story and ask a few questions about your career path. Could I ask for 30 minutes of your time over coffee or lunch to meet?

I understand you are very busy and if 30 minutes is not possible perhaps a 15 minute phone conversation is more manageable.

Please let me know a date and time that works best with your schedule.

Thank you for your time and I look forward to speaking soon,