diff --git a/include/boost/intrusive/avltree_algorithms.hpp b/include/boost/intrusive/avltree_algorithms.hpp
index 75e256d..3c98499 100644
--- a/include/boost/intrusive/avltree_algorithms.hpp
+++ b/include/boost/intrusive/avltree_algorithms.hpp
@@ -58,7 +58,7 @@ struct avltree_node_checker
    typedef bstree_node_checker<ValueTraits, NodePtrCompare, ExtraChecker> base_checker_t;
    typedef ValueTraits                             value_traits;
    typedef typename value_traits::node_traits      node_traits;
-   typedef typename node_traits::node_ptr          node_ptr;
+   typedef typename node_traits::const_node_ptr    const_node_ptr;
 
    struct return_type
          : public base_checker_t::return_type
@@ -71,7 +71,7 @@ struct avltree_node_checker
       : base_checker_t(comp, extra_checker)
    {}
 
-   void operator () (const node_ptr& p,
+   void operator () (const const_node_ptr& p,
                      const return_type& check_return_left, const return_type& check_return_right,
                      return_type& check_return)
    {
diff --git a/include/boost/intrusive/bstree.hpp b/include/boost/intrusive/bstree.hpp
index 9ae3cab..1b6ee5d 100644
--- a/include/boost/intrusive/bstree.hpp
+++ b/include/boost/intrusive/bstree.hpp
@@ -1854,7 +1854,7 @@ class bstree_impl
    }
 
    template <class ExtraChecker>
-   void check(ExtraChecker extra_checker)
+   void check(ExtraChecker extra_checker) const
    {
       typedef detail::key_nodeptr_comp<value_compare, value_traits> nodeptr_comp_t;
       nodeptr_comp_t nodeptr_comp(this->comp(), &this->get_value_traits());
@@ -1865,7 +1865,7 @@ class bstree_impl
          BOOST_INTRUSIVE_INVARIANT_ASSERT(this->sz_traits().get_size() == checker_return.node_count);
    }
 
-   void check()
+   void check() const
    {
       check(detail::empty_node_checker<ValueTraits>());
    }
diff --git a/include/boost/intrusive/bstree_algorithms.hpp b/include/boost/intrusive/bstree_algorithms.hpp
index 236ab8f..cf7a0a0 100644
--- a/include/boost/intrusive/bstree_algorithms.hpp
+++ b/include/boost/intrusive/bstree_algorithms.hpp
@@ -54,15 +54,15 @@ struct bstree_node_checker
    typedef ExtraChecker                            base_checker_t;
    typedef ValueTraits                             value_traits;
    typedef typename value_traits::node_traits      node_traits;
-   typedef typename node_traits::node_ptr          node_ptr;
+   typedef typename node_traits::const_node_ptr    const_node_ptr;
 
    struct return_type
       : public base_checker_t::return_type
    {
-      return_type() : min_key_node_ptr(node_ptr()), max_key_node_ptr(node_ptr()), node_count(0) {}
+      return_type() : min_key_node_ptr(const_node_ptr()), max_key_node_ptr(const_node_ptr()), node_count(0) {}
 
-      node_ptr min_key_node_ptr;
-      node_ptr max_key_node_ptr;
+      const_node_ptr min_key_node_ptr;
+      const_node_ptr max_key_node_ptr;
       size_t   node_count;
    };
 
@@ -70,7 +70,7 @@ struct bstree_node_checker
       : base_checker_t(extra_checker), comp_(comp)
    {}
 
-   void operator () (const node_ptr& p,
+   void operator () (const const_node_ptr& p,
                      const return_type& check_return_left, const return_type& check_return_right,
                      return_type& check_return)
    {
@@ -1487,9 +1487,9 @@ class bstree_algorithms
    }
 
    template<class Checker>
-   static void check(const node_ptr & header, Checker checker, typename Checker::return_type& checker_return)
+   static void check(const const_node_ptr& header, Checker checker, typename Checker::return_type& checker_return)
    {
-       node_ptr root_node_ptr = NodeTraits::get_parent(header);
+       const_node_ptr root_node_ptr = NodeTraits::get_parent(header);
        if (!root_node_ptr)
        {
            // check left&right header pointers
@@ -1503,7 +1503,7 @@ class bstree_algorithms
            // check subtree from root
            check_subtree(root_node_ptr, checker, checker_return);
            // check left&right header pointers
-           node_ptr p = root_node_ptr;
+           const_node_ptr p = root_node_ptr;
            while (NodeTraits::get_left(p)) { p = NodeTraits::get_left(p); }
            BOOST_INTRUSIVE_INVARIANT_ASSERT(NodeTraits::get_left(header) == p);
            p = root_node_ptr;
@@ -2069,10 +2069,10 @@ class bstree_algorithms
    }
 
    template<class Checker>
-   static void check_subtree(const node_ptr& node, Checker checker, typename Checker::return_type& check_return)
+   static void check_subtree(const const_node_ptr& node, Checker checker, typename Checker::return_type& check_return)
    {
-      node_ptr left = NodeTraits::get_left(node);
-      node_ptr right = NodeTraits::get_right(node);
+      const_node_ptr left = NodeTraits::get_left(node);
+      const_node_ptr right = NodeTraits::get_right(node);
       typename Checker::return_type check_return_left;
       typename Checker::return_type check_return_right;
       if (left)
diff --git a/include/boost/intrusive/detail/utilities.hpp b/include/boost/intrusive/detail/utilities.hpp
index cc7ed94..60fbbb7 100644
--- a/include/boost/intrusive/detail/utilities.hpp
+++ b/include/boost/intrusive/detail/utilities.hpp
@@ -311,11 +311,11 @@ struct empty_node_checker
 {
    typedef ValueTraits                             value_traits;
    typedef typename value_traits::node_traits      node_traits;
-   typedef typename node_traits::node_ptr          node_ptr;
+   typedef typename node_traits::const_node_ptr    const_node_ptr;
 
    struct return_type {};
 
-   void operator () (const node_ptr&, const return_type&, const return_type&, return_type&) {}
+   void operator () (const const_node_ptr&, const return_type&, const return_type&, return_type&) {}
 };
 
 template<class VoidPointer>
diff --git a/include/boost/intrusive/hashtable.hpp b/include/boost/intrusive/hashtable.hpp
index 65a6bf0..eb46167 100644
--- a/include/boost/intrusive/hashtable.hpp
+++ b/include/boost/intrusive/hashtable.hpp
@@ -2659,7 +2659,7 @@ class hashtable_impl
       return size_type(*bound);
    }
    /// @cond
-   void check() {}
+   void check() const {}
    private:
    size_traits &priv_size_traits()
    {  return static_cast<size_traits&>(static_cast<data_type&>(*this));  }
diff --git a/include/boost/intrusive/rbtree_algorithms.hpp b/include/boost/intrusive/rbtree_algorithms.hpp
index 5ebbd52..2c7529e 100644
--- a/include/boost/intrusive/rbtree_algorithms.hpp
+++ b/include/boost/intrusive/rbtree_algorithms.hpp
@@ -66,7 +66,7 @@ struct rbtree_node_checker
    typedef bstree_node_checker<ValueTraits, NodePtrCompare, ExtraChecker> base_checker_t;
    typedef ValueTraits                             value_traits;
    typedef typename value_traits::node_traits      node_traits;
-   typedef typename node_traits::node_ptr          node_ptr;
+   typedef typename node_traits::const_node_ptr    const_node_ptr;
 
    typedef typename base_checker_t::return_type    return_type;
 
@@ -74,7 +74,7 @@ struct rbtree_node_checker
       : base_checker_t(comp, extra_checker)
    {}
 
-   void operator () (const node_ptr& p,
+   void operator () (const const_node_ptr& p,
                      const return_type& check_return_left, const return_type& check_return_right,
                      return_type& check_return)
    {
diff --git a/include/boost/intrusive/treap.hpp b/include/boost/intrusive/treap.hpp
index 22ed24f..7170e45 100644
--- a/include/boost/intrusive/treap.hpp
+++ b/include/boost/intrusive/treap.hpp
@@ -905,14 +905,14 @@ class treap_impl
    }
 
    template <class ExtraChecker>
-   void check(ExtraChecker extra_checker)
+   void check(ExtraChecker extra_checker) const
    {
       typedef detail::key_nodeptr_comp<priority_compare, value_traits> nodeptr_prio_comp_t;
       nodeptr_prio_comp_t nodeptr_prio_comp(priv_pcomp(), &this->get_value_traits());
       tree_type::check(detail::treap_node_extra_checker<ValueTraits, nodeptr_prio_comp_t, ExtraChecker>(nodeptr_prio_comp, extra_checker));
    }
 
-   void check()
+   void check() const
    {
       check(detail::empty_node_checker<ValueTraits>());
    }
diff --git a/include/boost/intrusive/treap_algorithms.hpp b/include/boost/intrusive/treap_algorithms.hpp
index 73d1385..2c8f8e4 100644
--- a/include/boost/intrusive/treap_algorithms.hpp
+++ b/include/boost/intrusive/treap_algorithms.hpp
@@ -40,7 +40,7 @@ struct treap_node_extra_checker
    typedef ExtraChecker                            base_checker_t;
    typedef ValueTraits                             value_traits;
    typedef typename value_traits::node_traits      node_traits;
-   typedef typename node_traits::node_ptr          node_ptr;
+   typedef typename node_traits::const_node_ptr    const_node_ptr;
 
    typedef typename base_checker_t::return_type    return_type;
 
@@ -48,7 +48,7 @@ struct treap_node_extra_checker
       : base_checker_t(extra_checker), prio_comp_(prio_comp)
    {}
 
-   void operator () (const node_ptr& p,
+   void operator () (const const_node_ptr& p,
                      const return_type& check_return_left, const return_type& check_return_right,
                      return_type& check_return)
    {
diff --git a/test/test_container.hpp b/test/test_container.hpp
index eb0b32e..850ab5d 100644
--- a/test/test_container.hpp
+++ b/test/test_container.hpp
@@ -73,7 +73,7 @@ void test_container( Container & c )
       BOOST_TEST( it == itend );
       BOOST_TEST( c.size() == i );
    }
-   c.check();
+   static_cast<const Container&>(c).check();
 }