How do i contact cornerstone? Phone: (469) 621-6700 Fax: (469) 621-6678 Email: [email protected] Get in touch with Cornerstone Have questions or comments about our programs or hospitals? Please fill out the form below.Why choose corcornerstone for your executive search? Cornerstone is a global member of the Association of Executive Search and Leadership Consultants (AESC), Cornerstone is recognized as having the highest level of quality in the industry.Who is corcornerstone international group? Cornerstone International Group has executive search and leadership development professionals in 40 countries around the world. We also manage a global network of over 100 certified and highly qualified coaches.What services does cornerstone offer? Group and inpidual counseling and therapy for mental health needs are also provided by Cornerstone professionals. The organization is guided by an all-volunteer board of directors and has fostered partnerships with other local service providers.