Greg Lewis Achieves LEED AP Accreditation LEED Accredited Professionals (LEED APs) are building industry professionals who have demonstrated a thorough understanding of green building and the LEED Green Building Rating SystemTM. The LEED AP credential indicates that the professional has the knowledge and skills to facilitate the LEED certification process. LEED Professional Accreditation is a voluntary designation achieved by individuals who have passed the LEED Professional Accreditation exam.