It's all a British invention originally, ISO 9001, 9002 and 9003 are closely derived from BS 5750 parts 1, 2 and 3.
Compared to any other aviation management structure you'll actually not find it much different. You may find that your company FOB or equivalent standing orders book is called a "Quality Manual" or something similar, but the basic principle of best practice (or at-least working practice) being documented, followed, and periodically audited to make sure that's what you're really doing is nothing unusual to most aviation professionals.
For an aircraft operator, the biggest differences between what you've seen before and ISO9002 are likely to be twofold. Firstly you'll get periodically audited by the "accreditation body" as well as by the CAA and internally - the difference being that the accreditation body will be keener on checking that you're sticking to procedures, whilst the CAA is keener on checking that you're doing things safely, and simply tweaking procedures if you're not. Secondly, it won't just be the aircraft operations that are subject to procedures and auditing - accounts, publicity, sales, cleaning, etc. will all to a greater or lesser extent be subject to written procedures and periodic auditing (poor darlings ;-) )
How it works in practice varies from company to company. Good ones will use it to establish and stick to best working practice - some will be doing the absolute minimum to get accreditation because they really just need it to fulfil some contract or other and really don't care about it's usefulness. A few others (particularly those who have just gone ISO 9000 via a particularly over-enthusiastic quality manager) may be burying everybody under unnecessary procedures and paperwork in the name of "quality" - that usually only lasts a year or so but is profoundly irritating if you're in the middle of it.
G