The VMware Certified Implementation Expert (VCIX) is third-highest level in VMware's data center virtualization, cloud management and automation, desktop and mobility, and network virtualization certification tracks.
As of May 2015, the VMware certification tracks by degree of difficulty are VMware Certified Associate, VMware Certified Professional, VCIX and VMware Certified Design Expert. (VMware replaced the VMware Certified Advanced Professional level with the VCIX.)
VCP certification is a prerequisite for the VCIX level. The VCIX level tests candidates on their ability to develop a product-level design by collecting the business requirements, and then deploy the elements of that design. Candidates must pass two separate exams that evaluate the level of expertise in the implementation and design aspect.