The word hybrid typically has a positive connotation. Hybrid cars save fuel and are easier on our environment. Hybrid plants can create beautiful flower variations. Hybrid design can produce more interesting architecture. But hybrid IT?

In this case, the word hybrid doesn’t always come with a resounding sense of positivity. For many, even the simple idea of hybrid might cause a bit of nervousness; after all, it could mean disruption for your IT organization, which puts your digital business strategy at risk. Because that strategy is key to competing in today’s digital economy, anything that endangers it is worth better understanding. Here are five things all business leaders need to understand about hybrid IT:

1. What Is Hybrid IT?

At its most basic level, hybrid IT is a blend of cloud-based and on-premises IT services. The pursuit of standardization used to be a best practice for building IT architecture, as IT organizations prefer to manage only one type of computing. Due to pressures from both the business and IT to shift toward cloud services, however, hybrid IT has become more and more prevalent.

Think about all the cloud services your company currently uses — Dropbox, Salesforce, Workday and the like. Many of these services used to be provided by your IT organization through on-premises or home-grown applications, but they are now outsourced to cloud providers. Some smaller companies have also shifted toward a “cloud-first” approach for IT services, while others operate exclusively from the cloud. But most large enterprises have decades of IT investments that already work well. So, why replace it?

Although it might feel like everything is driven by the cloud these days, if you conducted a financial transaction online, checked in for a flight or stopped at a stoplight today, you used an IT service based on traditional computing — most likely one that included a mainframe.

Simply put, the cost and risk of migrating purpose-built applications to the cloud means that they may never move. As a result, most enterprises will maintain a hybrid IT environment for the foreseeable future.

2. Hybrid IT Introduces Complexity