Shopping for IT services can be tricky. The whole point is finding a professional firm that has more technical expertise than you do. But without all that specialized knowledge, it’s hard to know whether a service will deliver what your office needs. Things get even trickier when you start comparing providers who may be using different terms to describe very similar services.

One case in point is the term Managed IT Services, or Managed Services Provider (MSP), versus Cloud Services Provider (CSP). Some firms just call themselves MSPs or CSPs, while others may list both terms in their marketing material.

So, what’s the difference? MSPs handle all sorts of IT functions, from setting up a new network to troubleshooting an iPad that’s started acting strange. As more and more businesses are bringing some of their IT to the cloud—whether just for backup or email hosting or for their whole network infrastructure—some see CSPs as the wave of the future. Essentially, CSPs handle a company’s IT needs in the cloud. In many cases, that means they partner with one or more big cloud providers, figure out which services you can use, create a custom package for you and then keep it functioning smoothly.

Of course, even if everything is great in the cloud, you could still run into problems back in the office if an employee spills a mug full of coffee on his laptop. In many cases, what businesses need is some combination of MSP and CSP. And the good news is, that’s also what many IT firms offer. The bad news? The nature of their offerings isn’t always clear from their website or initial sales pitch. That’s why it’s important to have specific questions ready about the services they offer and the way they fit in with your business’s ways of operating.

Ultimately, you don’t have to be an IT expert to hire an IT expert. You just have to know what your company needs.