Quick -- which service providers give you the least trouble? Do you give higher marks to your banker or your home improvement contractor? Are you more satisfied by your doctor or your Internet service provider?

The folks at the Consumer Reports National Research Center recently released the results of their survey of service providers, and some of them are rather surprising. For example, while we're used to hearing horror stories about contractors, they earned a score of 86 out of 100, landing in second place on a list of service providers (after online electronics retailers).

While many people might scan through the list shaking their heads at the industries that didn't score well, as an investor, you might peruse the list and see opportunities. After all, if an industry (or a company within an industry) has a lot of room for improvement and actually improves, it's likely to be rewarded. Think, for example, of computer makers' tech support services, which landed in last place on the list, with a score of 59. I suspect that most of us are wary of such services by now, expecting hassles and headaches and trouble getting through to a live person. I myself had such expectations until recently, when my hard drive died. I ended up impressed with Dell's (NASDAQ:DELL) customer service. Dell has been working on improving its service and image, and as it succeeds, greater market share may well follow (followed, in turn, by greater profits and wealthier shareholders).

Here are some of the bottom-dwellers on the list (well, those in the bottom half of the list, anyway), followed by their scores:

  • Banks, 77
  • Supermarkets, 74
  • Airlines, 70
  • Internet service providers, 69
  • Cell-phone service, 66
  • TV service, digital cable, 66

Think about some of these industries and how they might improve. Where I live, for example, a popular bank has many branches that close their lobbies at 3 p.m. or 4 p.m. This certainly can't be convenient for many customers. (The bank I went with, Sovereign Bank (NYSE:SOV), keeps many of its lobbies open until 6 p.m. most days.) Commerce Bank (NYSE:CBH) is an example of a bank that gained a lot of attention and patronage by focusing on customer service -- opening on Sundays, for example, and keeping its drive-through window open until midnight on Fridays. (It appears to be under investigation by regulators at the moment, though.)

Airlines have increasingly been coming under attack lately, and with good reason. As Eric Horng reported for ABC News recently, "Cancellations doubled this summer compared to the same period last year, and nearly a third of all flights arrived late, the result of terrible weather, an outdated air traffic control system, near-record passenger volume, and inflexible airlines." So what have airlines been doing to improve their image? Continental Airlines (NYSE:CAL) is reportedly automatically rebooking customers who miss connecting flights on the next available flights. (I hope it's also working on drastically reducing the number of customers who miss connections in the first place.) JetBlue (NASDAQ:JBLU) is letting customers check their flights' status via cell phones and other digital devices. (Again, one hopes that the status is increasingly good.)

Meanwhile, cell-phone service providers also have considerable room for improvement. One main gripe from customers is the often-onerous termination fee charged if a customer wants out of a multiyear contract. A recent consumeraffairs.com article noted one customer who faced a $400 charge from Sprint Nextel (NYSE:S). Some providers are listening to the outcry. Verizon (NYSE:VZ), for example, is now pro-rating the fee, so that those with just a few months left pay less than those who recently signed up.

What to do
So now that you're thinking about companies' customer service, what should you do about it? Well, consider looking out for firms that are firming up their attention to customers. That's one of the things that Philip Durell does. He heads up our Motley Fool Inside Value newsletter, which can be tested for 30 days for free.

A few months back, for example, he recommended a major retailer, noting that "[w]inning over skeptics and persuading selective shoppers to do more of their buying at [the company's stores] is a central reason for the company's operational changes, planned store renovations, and merchandising changes. Store renovations are intended to reduce clutter; improve access and service to electronics, fashion apparel, and the pharmacy; and -- last but not least -- improve the washrooms! Pilot 'store within a store' layouts have improved sales of in-house apparel line ... [It] is not going upscale by any means, but it is open to introducing some higher-end items where the demographics warrant it."

So go ahead and seek out companies on your own that are beefing up their service. Or let us help you, via our newsletter recommendations.

Longtime Fool contributor Selena Maranjian does not own shares of any companies mentioned in this article. Dell is a Motley Fool Inside Value recommendation. Dell and JetBlue are Motley Fool Stock Advisor recommendations. Try any of our investing services free for 30 days. The Motley Fool is Fools writing for Fools.