Computer Work Station Monitor With Blank ScreenOne of the top tips to help you to select the best CMMS system for your business is to establish why you need a maintenance system and what you want from it.

The idea is to be prepared before you go and talk to potential providers. To help get you started this blog lists some of the outputs you may want to consider. It then looks at the inputs required to get them.

To simplify this I have broken down the workings of a CMMS into a diagram using the process model as a framework.

On the right are the outputs or functions of the system, the things you want it to give you. On the left are the inputs the system requires to give you those outputs.


The box at the top of the diagram represents the method by which the system operates; this is determined by the rules and analysis functions the software provider builds in.

At the bottom we can see an “improvement loop”. Certain outputs of the CMMS need to be fed back in to the input side as parameters change. Lessons learned and updates to schedules as a result of Planned Maintenance improving the equipment, are just two examples.

Outputs and functions

The 11 outputs and functions shown in the diagram are really category titles. Each one of these comprises a number of detailed items. A more thorough list can be found here.

While some of the outputs are really just retrieval of existing documents the clever part of the CMMS generates schedules for maintenance activities, conducts analysis on all the information collected and produces reports and forecasts to support decision making.

It’s important to decide what functions you want for your business before you investigate what is on the market. Answer the question “Why do we need it?” Use the detailed list to start a discussion with your team, but be selective.

Don’t be dazzled by the amazing functionality described by the provider if it’s really not what you need. Remember data and information that isn’t used is just expensive wallpaper.


CMMSs draw on a variety of data held in different databases. These are shown as the inputs on the right hand side of the diagram. An expanded list of these 7 categories can be found here.

Ideally the system you chose should integrate with the existing software and process control systems already used in your plant e.g. planning, asset management, parts inventory, parts location, purchasing, costing and escalation rules etc.

When you go shopping for your CMMS have a list of what systems you need it to integrate with.

The future

Over time you will need to expand your CMMS and make improvements to it as you review its ongoing use. Before you buy make sure the supplier can demonstrate that the system can be developed.

If you have any specific questions or suggestions about the list let me know.