diff --git a/cast.hpp b/cast.hpp
index b6166a7d..89ca2cb6 100644
--- a/cast.hpp
+++ b/cast.hpp
@@ -18,6 +18,8 @@
 #include <type_traits>
 #include <limits>
 
+#include <cstring>
+
 
 namespace cruft::cast {
     ///////////////////////////////////////////////////////////////////////////
@@ -222,4 +224,24 @@ namespace cruft::cast {
         cruft::debug::sanity (dst);
         return dst;
     }
+
+
+    /// Convert from SrcT to DstT by reinterpreting the bits that make up SrcT.
+    /// Effectively a reinterpret_cast of SrcT but without the undefined
+    /// behaviour.
+    ///
+    /// CXX#20: Convert instances of me to std::bit_cast when it becomes
+    /// available in supported compilers.
+    template <typename DstT, typename SrcT>
+    DstT
+    bit (SrcT &&src)
+    {
+        static_assert (sizeof (DstT) == sizeof (SrcT));
+        static_assert (std::is_trivially_copyable_v<std::decay_t<DstT>>);
+        static_assert (std::is_trivially_copyable_v<std::decay_t<SrcT>>);
+
+        DstT dst;
+        std::memcpy (&dst, &src, sizeof (DstT));
+        return dst;
+    }
 }