What is main difference between CLI and CLEI. I looked at Lotus site but I don't have a clue.
A CLI is a Certified Lotus Instructor, who is able to deliver Lotus Authorised content to clients in one of two streams, Application Development and/or System Administration, typically in the Lotus Notes/Domino platform. Courses that a CLI might deliver include "Domino Designer Fundamentals", or "Maintaining a Domino Server Infrastructure".
A CLEI is a Certified Lotus End-User Instructor, who is certified to deliver non-technical courses in Lotus software products, for example "Introducing the Notes Client" or "Working in Domino Databases".
The main difference between the two are their qualifications and the audience within their classes. CLI's are responsible for delivery of technical courses to System Administrators / Developers and hold at least Certified Lotus Professional qualifications in addition to Instructor certifications, while CLEI's facilitate courses for Notes end-users. Depending on the region that the CLEI is registered in they may also be a Certified Lotus Specialist.