diff --git a/gtsam/discrete/AlgebraicDecisionTree.h b/gtsam/discrete/AlgebraicDecisionTree.h
index 9769715a1..25e18cfaf 100644
--- a/gtsam/discrete/AlgebraicDecisionTree.h
+++ b/gtsam/discrete/AlgebraicDecisionTree.h
@@ -31,6 +31,8 @@ namespace gtsam {
    * Algebraic Decision Trees fix the range to double
    * Just has some nice constructors and some syntactic sugar
    * TODO: consider eliminating this class altogether?
+   *
+   * @ingroup discrete
    */
   template <typename L>
   class GTSAM_EXPORT AlgebraicDecisionTree : public DecisionTree<L, double> {
diff --git a/gtsam/discrete/Assignment.h b/gtsam/discrete/Assignment.h
index 90e2dbdd8..674c625ce 100644
--- a/gtsam/discrete/Assignment.h
+++ b/gtsam/discrete/Assignment.h
@@ -29,6 +29,7 @@ namespace gtsam {
  * An assignment from labels to value index (size_t).
  * Assigns to each label a value. Implemented as a simple map.
  * A discrete factor takes an Assignment and returns a value.
+ * @ingroup discrete
  */
 template <class L>
 class Assignment : public std::map<L, size_t> {
diff --git a/gtsam/discrete/DecisionTree.h b/gtsam/discrete/DecisionTree.h
index dede2a2f0..957a4eb48 100644
--- a/gtsam/discrete/DecisionTree.h
+++ b/gtsam/discrete/DecisionTree.h
@@ -38,6 +38,8 @@ namespace gtsam {
    * Decision Tree
    * L = label for variables
    * Y = function range (any algebra), e.g., bool, int, double
+   *
+   * @ingroup discrete
    */
   template<typename L, typename Y>
   class DecisionTree {
diff --git a/gtsam/discrete/DecisionTreeFactor.h b/gtsam/discrete/DecisionTreeFactor.h
index 86fa44649..bb9ddbd96 100644
--- a/gtsam/discrete/DecisionTreeFactor.h
+++ b/gtsam/discrete/DecisionTreeFactor.h
@@ -36,7 +36,9 @@ namespace gtsam {
   class DiscreteConditional;
 
   /**
-   * A discrete probabilistic factor
+   * A discrete probabilistic factor.
+   *
+   * @ingroup discrete
    */
   class GTSAM_EXPORT DecisionTreeFactor : public DiscreteFactor,
                                           public AlgebraicDecisionTree<Key> {
diff --git a/gtsam/discrete/DiscreteBayesNet.h b/gtsam/discrete/DiscreteBayesNet.h
index df94d6908..8ded827ce 100644
--- a/gtsam/discrete/DiscreteBayesNet.h
+++ b/gtsam/discrete/DiscreteBayesNet.h
@@ -33,7 +33,7 @@ namespace gtsam {
 
 /** 
  * A Bayes net made from discrete conditional distributions. 
- * @addtogroup discrete
+ * @ingroup discrete
  */
 class GTSAM_EXPORT DiscreteBayesNet: public BayesNet<DiscreteConditional> {
  public:
diff --git a/gtsam/discrete/DiscreteBayesTree.h b/gtsam/discrete/DiscreteBayesTree.h
index 809ce9c83..03a9a2fc7 100644
--- a/gtsam/discrete/DiscreteBayesTree.h
+++ b/gtsam/discrete/DiscreteBayesTree.h
@@ -62,7 +62,10 @@ class GTSAM_EXPORT DiscreteBayesTreeClique
 };
 
 /* ************************************************************************* */
-/** A Bayes tree representing a Discrete density */
+/**
+ * @brief A Bayes tree representing a Discrete density.
+ * @ingroup discrete
+ */
 class GTSAM_EXPORT DiscreteBayesTree
     : public BayesTree<DiscreteBayesTreeClique> {
  private:
diff --git a/gtsam/discrete/DiscreteConditional.h b/gtsam/discrete/DiscreteConditional.h
index cff1b69a6..6a286633d 100644
--- a/gtsam/discrete/DiscreteConditional.h
+++ b/gtsam/discrete/DiscreteConditional.h
@@ -32,6 +32,8 @@ namespace gtsam {
 /**
  * Discrete Conditional Density
  * Derives from DecisionTreeFactor
+ *
+ * @ingroup discrete
  */
 class GTSAM_EXPORT DiscreteConditional
     : public DecisionTreeFactor,
diff --git a/gtsam/discrete/DiscreteDistribution.h b/gtsam/discrete/DiscreteDistribution.h
index c5147dbc1..bf3f1c9ae 100644
--- a/gtsam/discrete/DiscreteDistribution.h
+++ b/gtsam/discrete/DiscreteDistribution.h
@@ -27,6 +27,8 @@ namespace gtsam {
 /**
  * A prior probability on a set of discrete variables.
  * Derives from DiscreteConditional
+ *
+ * @ingroup discrete
  */
 class GTSAM_EXPORT DiscreteDistribution : public DiscreteConditional {
  public:
diff --git a/gtsam/discrete/DiscreteEliminationTree.h b/gtsam/discrete/DiscreteEliminationTree.h
index 1ea8a5695..a28054615 100644
--- a/gtsam/discrete/DiscreteEliminationTree.h
+++ b/gtsam/discrete/DiscreteEliminationTree.h
@@ -24,6 +24,10 @@
 
 namespace gtsam {
 
+  /**
+   * @brief Elimination tree for discrete factors.
+   * @ingroup discrete
+   */
   class GTSAM_EXPORT DiscreteEliminationTree :
     public EliminationTree<DiscreteBayesNet, DiscreteFactorGraph>
   {
diff --git a/gtsam/discrete/DiscreteFactor.h b/gtsam/discrete/DiscreteFactor.h
index 212ade8cf..c6bb079fb 100644
--- a/gtsam/discrete/DiscreteFactor.h
+++ b/gtsam/discrete/DiscreteFactor.h
@@ -31,6 +31,8 @@ class DiscreteConditional;
 /**
  * Base class for discrete probabilistic factors
  * The most general one is the derived DecisionTreeFactor
+ *
+ * @ingroup discrete
  */
 class GTSAM_EXPORT DiscreteFactor: public Factor {
 
diff --git a/gtsam/discrete/DiscreteFactorGraph.h b/gtsam/discrete/DiscreteFactorGraph.h
index bfa57e7db..818eeda4e 100644
--- a/gtsam/discrete/DiscreteFactorGraph.h
+++ b/gtsam/discrete/DiscreteFactorGraph.h
@@ -40,7 +40,14 @@ class DiscreteEliminationTree;
 class DiscreteBayesTree;
 class DiscreteJunctionTree;
 
-/** Main elimination function for DiscreteFactorGraph */
+/**
+ * @brief Main elimination function for DiscreteFactorGraph.
+ * 
+ * @param factors 
+ * @param keys 
+ * @return GTSAM_EXPORT
+ * @ingroup discrete
+ */
 GTSAM_EXPORT std::pair<boost::shared_ptr<DiscreteConditional>, DecisionTreeFactor::shared_ptr>
 EliminateDiscrete(const DiscreteFactorGraph& factors, const Ordering& keys);
 
@@ -64,6 +71,7 @@ template<> struct EliminationTraits<DiscreteFactorGraph>
 /**
  * A Discrete Factor Graph is a factor graph where all factors are Discrete, i.e.
  *   Factor == DiscreteFactor
+ * @ingroup discrete
  */
 class GTSAM_EXPORT DiscreteFactorGraph
     : public FactorGraph<DiscreteFactor>,
diff --git a/gtsam/discrete/DiscreteJunctionTree.h b/gtsam/discrete/DiscreteJunctionTree.h
index c74ad3cc2..f417cf6fa 100644
--- a/gtsam/discrete/DiscreteJunctionTree.h
+++ b/gtsam/discrete/DiscreteJunctionTree.h
@@ -44,7 +44,8 @@ namespace gtsam {
    * The tree structure and elimination method are exactly analogous to the EliminationTree,
    * except that in the JunctionTree, at each node multiple variables are eliminated at a time.
    *
-   * \addtogroup Multifrontal
+   * \ingroup Multifrontal
+   * @ingroup discrete
    * \nosubgrouping
    */
   class GTSAM_EXPORT DiscreteJunctionTree :
diff --git a/gtsam/discrete/DiscreteKey.h b/gtsam/discrete/DiscreteKey.h
index dea00074d..40343d21f 100644
--- a/gtsam/discrete/DiscreteKey.h
+++ b/gtsam/discrete/DiscreteKey.h
@@ -30,6 +30,7 @@ namespace gtsam {
   /**
    * Key type for discrete variables.
    * Includes Key and cardinality.
+   * @ingroup discrete
    */
   using DiscreteKey = std::pair<Key,size_t>;
 
diff --git a/gtsam/discrete/DiscreteLookupDAG.h b/gtsam/discrete/DiscreteLookupDAG.h
index 15169a1dc..b7f900073 100644
--- a/gtsam/discrete/DiscreteLookupDAG.h
+++ b/gtsam/discrete/DiscreteLookupDAG.h
@@ -32,6 +32,7 @@ class DiscreteBayesNet;
 
 /**
  * @brief DiscreteLookupTable table for max-product
+ * @ingroup discrete
  *
  * Inherits from discrete conditional for convenience, but is not normalized.
  * Is used in the max-product algorithm.
diff --git a/gtsam/discrete/DiscreteMarginals.h b/gtsam/discrete/DiscreteMarginals.h
index dc87f665e..7bb2cc6f8 100644
--- a/gtsam/discrete/DiscreteMarginals.h
+++ b/gtsam/discrete/DiscreteMarginals.h
@@ -28,6 +28,7 @@ namespace gtsam {
 
   /**
    * A class for computing marginals of variables in a DiscreteFactorGraph
+   * @ingroup discrete
    */
 class DiscreteMarginals {
 
diff --git a/gtsam/discrete/DiscreteValues.h b/gtsam/discrete/DiscreteValues.h
index cb17bf833..72bb24081 100644
--- a/gtsam/discrete/DiscreteValues.h
+++ b/gtsam/discrete/DiscreteValues.h
@@ -36,6 +36,7 @@ namespace gtsam {
  * Another good thing is we don't need to have the special DiscreteKey which
  * stores cardinality of a Discrete variable. It should be handled naturally in
  * the new class DiscreteValue, as the variable's type (domain)
+ * @ingroup discrete
  */
 class GTSAM_EXPORT DiscreteValues : public Assignment<Key> {
  public:
diff --git a/gtsam/discrete/Signature.h b/gtsam/discrete/Signature.h
index ff83caa53..3138435a9 100644
--- a/gtsam/discrete/Signature.h
+++ b/gtsam/discrete/Signature.h
@@ -48,6 +48,8 @@ namespace gtsam {
    *   (E|T,L) = "F F F 1"
    *   X|E = "95/5 2/98"
    *   (D|E,B) = "9/1 2/8 3/7 1/9"
+   *
+   * @ingroup discrete
    */
   class GTSAM_EXPORT Signature {