Commentary on Sections Part 3: Planning Control. Section 40: Form and content of applications
The format of applications for planning permission is governed by this section.  A development order may specify the information and documents which must accompany an application and the form and content of it.  This section requires certain applications for planning permission and consent to be accompanied by a statement about the design principles and concepts that have been applied to the development and a statement about how issues relating to access to the development have been dealt with.