Bankruptcy is an option for people with insurmountable debts.
The people who benefit from it most are those with no or few assets, with unsecured debts.
Your DH would be 'bankrupt' for up to a year, but depending on an assessment of incomings and outgoings would need to contribute to his debt for up to 3 years.
This compares with an IVA which requires a 5 year committment.
The note of insolvency lasts 6 years after last entry.
So, for bankruptcy, his 'credit rating' would be marked for 7 yrs, for an IVA 11 yrs.
Some effects of bankruptcy last a lot longer than others. For example, getting any sort of credit will be very hard. Having said that, anyone who has benefitted from bankruptcy on a personal level (ie. it has changed their lives and given them a 'clean start') has, in my experience, been completely put off credit for life!
DH and I filed bankruptcy in 2007. Discharged the same year (9 months and 10 months respectively). Had no assets, no excess income to speak of, so didn't need a Payment Agreement.
We were allowed to keep both (old) cars because we worked in opposite directions at conflicting times and had no access to reliable public transport (DH worked off-route and I worked at a time which was impossible for a bus journey). The Official Receiver decided it would be silly to demand we give up a car because to do so would stop us earning an income.
We have a bank account. Never been overdrawn in nearly 5 years now. We have a debit card, can set up Standing Orders, Direct Debits, etc. We don't, nor will ever, have an overdraft - wouldn't take credit under any circumstances now.
We have been able to take out a contract for a TV subscription (BT Vision) but had to jump through a few hoops to do so. Generally, you would fail first credit check, but then the more indepth assessment is fine, when they can see that you have no credit, 5 years good history, etc.
For us, it was the best move. We couldn't survive with the debts we had, and we couldn't escape the situation we were in. Even with an IVA we would have been sunk.
Having said that, if your husband has a good job, and only £18k debt, there are other options, and an IVA is one of those. The other is asking CAB to intervene and get interest rates frozen, etc.