Everyone should have underinsured motorist coverage.  Recently settled UIM claim where client was struck by a drunk driver.  The drunk driver only had minimum liability coverage, i.e. $25,000 per injured person, maximum of $50k total per accident.  So, when multiple vehicles are involved and/or multiple people are injured in the accident, the liability coverage available to victims is limited.  My client was the only party seriously injured in the accident so we were able to collect full $25k for her from the drunk driver's insurer, and further, because she had purchased UIM coverage as part of her auto insurance coverage, we were able to collect the full amount of that policy while dramatically reducing subrogation claims, putting more money in our client's pocket.    Case was complicated by pre-existing back injury (accident damaged hardware from previous back surgery); client was driving for work when accident occurred (so workers comp insurance involved); and health insurer paid claims that should have been paid by comp carrier.  It was a real mess sorting it all out but we got it done.