We build web apps that in turn interact with other applications to capture, store, retrieve, edit, and visualise data.
A CMS is one type of application. We are experts at building them. We are also experts at building applications that interact with CMSs and other systems. Often, especially with enterprise-level projects, a legacy system may need to stay in place and new systems built on top of it or to interact with it in various ways. One example is building an interface to interact with a CRM that is used to keep data on customers. Another may be creating a Facebook application so your online-store can trade on Facebook. Or you may decide to use something like Google Apps to store your website's content, a CMS to display it, and something (our expertise?) to build a bridge between the two.
We have built many systems that use one system for data, one for customer interaction, and another for displaying all of this information. It's a big task, the kind where sleeves must be rolled up, heads scratched, and elbows greased; the kind that we excel at.