Connect-a-Colleague is an easy-to-use referral tool that links members' colleagues to the Society. By simply entering a colleague's name and email, ASHRAE members can have a prewritten invitation to join ASHRAE sent on their behalf. Users have the option to add a custom message, and reference a technical committee section that may be of interest to their colleague. Member referrals are the top reason new members join ASHRAE.

https://www.ashrae.org/membership--conferences/connect-a-colleague