The important of OD and how it began

Discuss the important of OD and how it began up to now.
(2) Discuss the future of OD.
(3) Discuss what OD has to do with Change management.
(4) Discuss what OD has to do with OD Consultants/Practitioners.
(5) Discuss what skills/knowledge an OD Consultants/Practitioners must have to help organizations achieve their OD goals