Open source, but fully supported.
Concrete CMS is free and open source under the MIT license, and is fully ISO:27001 compliant out of the box. If your organization's IT and compliance groups want to manage the platform yourself, you're welcome to!
If your team would rather focus on content, the team behind Concrete can host your website for you and help you maintain a safe, secure and compliant web presence. We have a detailed understanding of compliance requirements and security is baked into our processes from the ground up. You'll be able to sleep soundly knowing our people are watching out for your public presence on the web.
Support contracts are here to provide value & safety when you need it, but are never a requirement. You'll never get roped into some license fee you don't understand and can't control. You'll always own your content and your copy of the CMS, we're just eager to help if we can provide value.