diff --git a/doc/RTD/source/ParameterFiles/index.rst b/doc/RTD/source/ParameterFiles/index.rst
index ec5ce1ab41197b6ca6fa5da2cbde7666383f82e9..507e188b307474adb870ee29e0fd8e400ff7f90e 100644
--- a/doc/RTD/source/ParameterFiles/index.rst
+++ b/doc/RTD/source/ParameterFiles/index.rst
@@ -181,6 +181,13 @@ flag) this section of the YAML file is entirely ignored.
 Gravity
 -------
 
+The behaviour of the self-gravity solver can be modifed by the parameters
+provided in this section. The theory document puts these parameters into the
+context of the equations being solved. We give a brief overview here.
+
+* The co-moving softening used for all particles :math:`\epsilon_{c}`: ``comoving_softening``
+* The 
+
 SPH
 ---