I'm an IT Contractor - How Will A Professional Indemnity Policy Protect Me?

The point of professional indemnity insurance is to protect you from the consequences of mistakes you might make in your professional capacity. A statement which raises two important questions. What type of mistakes? What sort of consequences?
Typically, indemnity insurance provides cover against acts of negligence, error or omission; the accidental loss or destruction of a client's data or documentation; unintentional breach of confidence; inadvertent infringement of intellectual property rights; unintentional libel or slander.
Now, as an IT contractor, you're unlikely to need pi insurance cover for the last one. But you don't need to stretch your imagination too far to see how all of the rest could be relevant to you.
A coding error that causes a critical application to repeatedly crash resulting in costly delays to a project. A misunderstanding of a client's brief leading to a system configuration that fails to meet the required specifications. Confusion over the existence (or otherwise) of backed-up files leading to the accidental, and permanent, deletion of a key database. A casual chat about a client's confidential IT plans with another contractor who, unbeknownst to you, happens to be working for a competitor. The incorporation of what you thought was freeware (but wasn't) in a system for a client against whom a legal action is subsequently brought.
Incidents like these can happen all too easily. Which brings us to the point about consequences? Because incidents like these can all too easily lead to you being sued. In an increasingly litigious world, claim all too often follows blame. And the value of the claims made can be staggeringly high. Why? Because the client, or the client's lawyers, will include in the claim every conceivable loss resulting from your mistake - from lost revenues to the cost of remedial work to the financial impact of damage to reputation.
Talking of lawyers, even if you think you have a strong case against the claim, without professional indemnity cover it will be down to you to fund what will undoubtedly be a very costly defense. Of course, if you win the case, you may well get your costs reimbursed. But is your cash flow strong enough to bridge a gap caused by lawyers' fees?
And if you lose the case ... well, then you will be faced not just with your own legal fees but that staggeringly high compensation award and the client's legal fees as well. More than enough, quite possibly, to bankrupt you.
So that's how professional indemnity insurance can protect you.