NASEO's members are senior officials from the 56 State and Territory Energy Offices, as well as affiliates from the private and public sectors. NASEO is the only national non-profit organization whose membership includes the governor-designated energy officials from every state and territory.  

NASEO's Affiliate Members include representatives from business, trade associations, nonprofit organizations, educational institutions, and government. Affiliate Members offer NASEO a valuable resource in their diversity of perspective on emerging energy issues, which contributes greatly to our success in promoting a balanced approach to energy issues.