We'll detail everything you need to know about how to invite a guest speaker, from the earliest planning stages to drafting a formal speaker invitation letter. On behalf of the XYZ and the XYZ Organizing Committee, we are honored to invite you to speak at the XYZ event celebrating Cybersecurity Career Week (CCW).We are excited to invite you to join us as a featured speaker at this event. How to fill out the Formal Invitation Letter to Guest Speaker Dr. Emily Thompson? Your invitation should be a formal email (or letter). Outline the reasons why you've chosen them as the best person to speak at your event. - In the opening paragraph, briefly introduce yourself and state the purpose of the letter. Montefiore Medical Group. Healthcare Training in the Bronx. One Professional Letter of Recommendation Required.