diff --git a/doc/doxygen/groups/main.md b/doc/doxygen/groups/main.md
index 14b7c448ed4455ab5ec43ef86d2570e7b3d2a40e..283a0a2bdbe0ffbb1f007a432564256e252f5a20 100644
--- a/doc/doxygen/groups/main.md
+++ b/doc/doxygen/groups/main.md
@@ -10,9 +10,23 @@
 
 @defgroup Parameter Parameters and runtime configuration
 
-@defgroup Material Constitutive modeling
-@brief Constitutive model framework - Constitutive relations for fluids, solids, fluid-matrix-interactions and more
-@details Constitutive relations formalize the functional dependence among physical variables, thereby providing the missing equations to close systems.
+@defgroup Material Constitutive models
+@brief Constitutive relations for fluids, solids, fluid-matrix interactions, and more
+@details Constitutive relations formalize the functional dependence among physical variables, thereby providing the missing equations to close systems. Some constitutive relations, in particular if they are ad-hoc (e.g. Hooke's law) or empirical
+and not derived from basic principles, are also called material laws.
+Implementations of the functional relationships available in DuMu<sup>x</sup> are collected in the folder `dumux/material`.
+
+Most implementations follow one of the following paradigms
+
+* free functions (in nested namespaces),
+* stateless classes with static member functions where all parameters are function arguments,
+* statefull classes that contain parameters that need to be initialized.
+
+Stateless, purely static classes have the advantage that only the class type needs to be known to
+the class using them. Statefull classes need to be instantiated
+and the instantiated object is passed to the consumer class.
+
+To view the description of individual constitutive models and classes, click on one the modules below.
 
 @defgroup MultiDomain Multidomain framework
 @brief Coupling of several regular DuMu<sup>x</sup> problems
diff --git a/doc/doxygen/groups/material.md b/doc/doxygen/groups/material.md
index 3d058a9fc4d3f75f271348511dd3e0e32f57b72e..82e528fc07c6c37b520bc9f7db33985c46eb03bc 100644
--- a/doc/doxygen/groups/material.md
+++ b/doc/doxygen/groups/material.md
@@ -17,7 +17,7 @@
 <!-- Components -->
 
 @defgroup Components Thermodynamical properties of chemical species
-@brief Thermodynamical properties of single chemical species or fixed mixtures of species (\f$ \text{CO}_2, \text{H}_2\text{O}, \text{Air}, ... \f$)
+@brief Thermodynamical properties of single chemical species or fixed mixtures of species ($ \text{CO}_2, \text{H}_2\text{O}, \text{Air}, ... $)
 @details Components provide the thermodynamic relations for the liquid, gaseous and/or solid state of a single
 chemical species or a _fixed_ mixture of species. Fluid systems use components to compute thermodynamic quantities of phases. An example would be the dynamic viscosity at different temperatures and pressures.
 @ingroup Material
@@ -45,8 +45,8 @@ chemical species or a _fixed_ mixture of species. Fluid systems use components t
 <!-- Fluidmatrixinteractions -->
 
 @defgroup Fluidmatrixinteractions Fluid-matrix interactions
-@brief Constitutive relations such as pc-Sw relations, kr-Sw relations, effective diffusion coefficients, friction laws
-@details Constitutive models for interaction of fluids and solids. The relations depend on the fluid state as well as material parameters of the matrix. For example, in porous media theory, the effective heat conductivity depends on the solid heat conductivity, the fluid heat conductivity, as well as the porosity of the solid and the fluid saturation.
+@brief Constitutive models for interaction of fluids and solids
+@details This module includes constitutive relations such as pc-Sw relations, kr-Sw relations, effective diffusion coefficients, friction laws. The relations depend on both the fluid state as well as material parameters of the solid matrix. For example, in porous media theory, the effective heat conductivity depends on the solid heat conductivity, the fluid heat conductivity, as well as the porosity of the solid and the fluid saturation.
 @ingroup Material
 
 <!-- Fluidmatrixinteractions subgroups  -->