The ability to incorporate markup from multiple markup files in rendering the view for a single request has been called "Multi-File Templates" (MFT) and is a powerful new features that was added to RSF in version 0.7.

Unlike similar systems in other template-based frameworks, RSF's concept of MFT is not tied to any particular conception of a user interface "widget" or "component", but is in fact a very general scheme for aggregating markup, driven only by correspondance of names (rsf:ids).

The RSF system of Evolvers, explained in detail with BuildingRSFComponents is one convention for driving MFT, which gives a result similar to that of user "widgets" familiar from other frameworks.

The RSF system of OuterPageTemplates is another, giving a result similar to that of page templates or "layouts".

The user of RSF is free to set up any other kinds of scheme they find desirable for organising markup and component aggregation, limited only by the possibilities of Spring injection - that is, "boundlessly limited" :)