1. In the US:
1.1. Regional and National Accreditation (RA & NA): A higher education institution (I will say "university" hereafter) needs to be ?accredited? by either a National or a Regional Accreditation Agency which is recognized by CHEA. This is almost mandatory for a university since neither a state nor federal government recognizes the degrees issued by ?unaccredited? universities i.e. those holding neither of the 2 types of aforementioned accreditations. Unaccredited institutions in this sense can be called ?degree mills?, ?fake?, or etc.
1.2. Program/Subject Based Accreditation: These are programme-specific or subject-specific accreditations, which are not mandatory requirements generally, however seem to provide significant added prestige and value to the degrees issued. Within the concept of this site, the most well-known examples are AACSB, AMBA and EQUIS (Details can be discussed), among which AACSB is the prominent one in the US. Universities without any of these accreditations are not necessarily deemed ?degree mills?, as long as they have RA or NA, however when it comes to academic prestige, having one seems to be a big plus.
2. In the UK:
2.1. The Quality Assurance Agency for Higher Education (QAA): Independently reviews the universities, makes assessments and publishes reports, emphasizing good practices and points of improvement, which can also be programme or school-specific. Undertakes an advisory role for relevant UK government authorities. ??QAA is the body entrusted with advising the Privy Council of the United Kingdom, via government ministers, on which institutions should be granted degree awarding powers and the right to be called a university.
(?) QAA has cooperation agreements with a number of other educational bodies and quality assurance agencies, both in the UK and internationally??(taken from http://en.wikipedia.org/wiki/QAA)
2.2. Program/Subject Based Accreditation: See 1.2. In this case, the more prominent body seems to be AMBA. Generally speaking, the penetration of this type of accreditation among UK universities seems to be relatively lower when compared to the situation in the US, with many universities including some highly reputable ones having none.
2.3. As it seems, the counterpart of ?mandatory accreditation? in the US, which is RA&NA, seems to be the ?approval of QAA? in the UK, which, by definition is not an ?accrediting body? but a ?quality assurance agency?.
(Not exactly the same, of course, since different regulatory practices are in place)
In a nutshell, a UK university (or programme) with QAA approval (a positive report), though may not have been ?accredited?, is not ?unaccredited? in the context of American accreditation.
The reason for me to share this post is that I came across too much confusion on this topic at various websites and since this site seems to have a significant amount of traffic, I thought it would be useful to start a discussion here.