National Insurance Number needed to start employment?

I searched the forum but couldnt find any relevant posts so apologies if this has been discussed before. My husband and I will be landing in UK on Dec 28th. My question is to do with applying for the National Insurance number. From basic research i see that it can take anywhere from 8 weeks to even months and a few of my friends settled there tell me that many organizations dont let you work for them unless you have a National Insurance number, can someone please shed light on this?
Does it make sense to use some kind of agent to expediate the process and is it necessary to have a National Insurance number before you can start working?

Thanks
Simi

You dont 'literally' need the NI number if you have proof that you have applied for one. So come here, start the NI process and you will have proof you will be getting it in 8 weeks or so.
Employers understand NI takes time so need affirmation that you have applied for it thats all
Also note that by the time you settle in and secure a role, if permanent, will take close to 4-8 weeks to get everything sorted out so NI wont be a deal breaker

Cheers
KP

Thanks kp - much relieved now. Was worried that we would be without jobs for months till we wait for NI.