diff --git a/include/gz/sim/Model.hh b/include/gz/sim/Model.hh
index c3b668ac02..9de49ea0a1 100644
--- a/include/gz/sim/Model.hh
+++ b/include/gz/sim/Model.hh
@@ -126,18 +126,16 @@ namespace gz
       /// \param[in] _ecm Entity-component manager.
       /// \param[in] _name Joint name.
       /// \return Joint entity.
-      /// \todo(anyone) Make const
       public: sim::Entity JointByName(const EntityComponentManager &_ecm,
-          const std::string &_name);
+          const std::string &_name) const;
 
       /// \brief Get the ID of a link entity which is an immediate child of
       /// this model.
       /// \param[in] _ecm Entity-component manager.
       /// \param[in] _name Link name.
       /// \return Link entity.
-      /// \todo(anyone) Make const
       public: sim::Entity LinkByName(const EntityComponentManager &_ecm,
-          const std::string &_name);
+          const std::string &_name) const;
 
       /// \brief Get all joints which are immediate children of this model.
       /// \param[in] _ecm Entity-component manager.
diff --git a/src/Model.cc b/src/Model.cc
index c27ea760ec..a23779981f 100644
--- a/src/Model.cc
+++ b/src/Model.cc
@@ -130,7 +130,7 @@ std::string Model::SourceFilePath(const EntityComponentManager &_ecm) const
 
 //////////////////////////////////////////////////
 Entity Model::JointByName(const EntityComponentManager &_ecm,
-    const std::string &_name)
+    const std::string &_name) const
 {
   return _ecm.EntityByComponents(
       components::ParentEntity(this->dataPtr->id),
@@ -140,7 +140,7 @@ Entity Model::JointByName(const EntityComponentManager &_ecm,
 
 //////////////////////////////////////////////////
 Entity Model::LinkByName(const EntityComponentManager &_ecm,
-    const std::string &_name)
+    const std::string &_name) const
 {
   return _ecm.EntityByComponents(
       components::ParentEntity(this->dataPtr->id),