| assignment | An interface to the assignment table in the database |
| BusinessAdmin | Provides basic functions like adding elements to the database |
| client | An interface to the client table in the database |
| constants | A class for some constants |
| contact | An interface to the contact table in the database |
| correspondence | An extension of FPDF to generate personalized correspondence PDFs |
| file | An interface to the file table in the database |
| offer | An interface to the offer table in the database |
| response | Provides a standard to base all responses to be called with AJAX on |