Six Sigma was created by Motorola in 1985 (and is a registered trademark) to create a structured approach to process improvement by reducing the defect rate and minimizing variability in manufactured products. It encompasses a range of techniques for quality management and defines various levels of experts in the processes to implement them. These experts are named similarly to karate (green belt, black belt, etc.). It was named six sigma because it was based on a desired manufacturing defect rate of 0.00034, or 3.4 defects per million items produced, and though the concept has spread to many areas far from manufacturing over the years, the name has remained the same. There is no standard certification body (similar to ITIL) that defines exactly what is required to be certified at any specific level, and thus training and certification can vary widely, from for-profit organizations to non-profit organizations to universities. It is very important to find a well-known provider for the certification to carry much weight in the job market.
Another widely accepted program is run by the non-profit group ASQ (the American Society for Quality, now known by the acronym only, as they are a worldwide organization). They offer certifications in many areas related to various aspects of quality, including six sigma. Their certification program is CSSBB (Certified Six Sigma Black Belt) for the black belt level; they also offer a green belt level (the CSSGB). They require documentation of completing at least one six sigma project in addition to passing an exam and then maintaining the certification by either getting at least 18 credits over a three-year period (attainable via activities such as attending conferences, taking classes, or teaching the skills to others) or by retaking the exam if the credits were not earned in the mandated time frame. For information on ASQ's CSSBB certification, please refer to http://prdweb.asq.org/certification/control/index.
IT is a very fast-changing industry - what is hot today may be a tiny niche market in only a few years and things that few have heard of may be huge trends in the same timeframe. That having been said, many certifications have a long life span, by which we don't mean that the certification is good for many years before it expires, but rather that the certification has been around and will be around (as best as the future is predictable) for a long time. This does not imply that recertification on new versions and/or continuing education credits are not required to maintain certification, however. Predicting the future is always challenging, not the least a future in IT, but these certifications are good bets.
The top 10 certifications that meet this criterion (in no particular order), identified by Global Knowledge instructor John Hales, include the following. Note that the certifications are broad in terms of topics covered and are not all strictly IT administrator-based.