Both ResourceFirst and Portfolio Desktop allow Overhead items to be defined and actual time recorded against those items. This is often used for administrative items which are not actively managed with forecasts or baselines. Overhead items allow for a resource’s full activities to be accounted for in time tracking, but those items do not show up in the project portfolio. Examples might include Meetings, Paid Time Off, etc.
Sometimes it is useful to manage these administrative items actively as projects, so that they show up in the portfolio. To do this, just define a project for each item (It can be an annual project or even quarterly). Or create a "bucket project" with each of the overhead types as tasks. A good rule of thumb is that heavy, planned, ongoing work, such as general support, operational maintenance, or consulting are best forecasted and tracked via departmental-level projects.
It may be useful to put the overhead-type projects in a special node in the Project OBS to facilitate easy usage and rights administration. In this case, these “overhead” projects can be actively managed (i.e., have forecasts, baselines, and actuals recorded against them in ResourceFirst or Portfolio Desktop), just like other projects.