Once it's up and running, the ISA system would probably mean you have to be ISA-registered before you can work as a childminder, or employ childminders. (I say probably, because while employers such as schools will HAVE to only employ ISA-registered teachers, it's possible that parents will be allowed to employ non-ISA-registered nannies/childminders if they want - have looked on the website but can't find the answer to this, maybe they don't know yet.)
However, as a professional child-carer, you would want to be ISA-registered anyway because not having it would suggest you don't take your career seriously and would massively limit your job options.
Timingwise, the ISA website is cagey about when it's coming into force (I think it's taking a while to set up) and when it does, it will be phased, ie a school wouldn't have to immediately fire all its teachers because they aren't ISA-registered yet.
As a self-employed childminder, you would be responsible for registering yourself, so that parents could check your ISA status when considering using you. (Parents can't see what your record says about you - only the fact that you are either ISA-registered or not.)
The USPS of the ISA will be:
- it combines several existing exclusion lists of people who mustn't work with children, in one place
- it's continuously updated, thus if I as a mum hire a nanny/childminder who abuses my child, I would be responsible for informing the ISA so that they can update the person's details, and if necessary bar them, so that they can no longer work with children/vulnerable adults.
Re CRB checks, the ISA and CRB are working closely together but I'm not 100% clear on how the need for a CRB check will fit with being ISA-registered. Possibly, when you apply for ISA registration, the ISA will look at results of your previous checks, but if you need a new one for a specific job, it's up to you to get one. But don't quote me on that!