diff --git a/capnp/capnp.pyx b/capnp/capnp.pyx
index 0308992..bd233da 100644
--- a/capnp/capnp.pyx
+++ b/capnp/capnp.pyx
@@ -8,7 +8,7 @@
 cimport cython
 cimport capnp_cpp as capnp
 cimport schema_cpp
-from capnp_cpp cimport SchemaLoader as C_SchemaLoader, Schema as C_Schema, StructSchema as C_StructSchema, DynamicStruct as C_DynamicStruct, DynamicValue as C_DynamicValue, Type as C_Type, DynamicList as C_DynamicList, DynamicUnion as C_DynamicUnion, fixMaybe, SchemaParser as C_SchemaParser, ParsedSchema as C_ParsedSchema, VOID, ArrayPtr, StringPtr
+from capnp_cpp cimport SchemaLoader as C_SchemaLoader, Schema as C_Schema, StructSchema as C_StructSchema, DynamicStruct as C_DynamicStruct, DynamicValue as C_DynamicValue, Type as C_Type, DynamicList as C_DynamicList, DynamicUnion as C_DynamicUnion, fixMaybe, fixMaybeUnion, SchemaParser as C_SchemaParser, ParsedSchema as C_ParsedSchema, VOID, ArrayPtr, StringPtr
 
 from schema_cpp cimport CodeGeneratorRequest as C_CodeGeneratorRequest, Node as C_Node, EnumNode as C_EnumNode
 from cython.operator cimport dereference as deref
@@ -278,7 +278,6 @@ cdef toPython(C_DynamicValue.Builder & self, object parent):
     else:
         raise ValueError("Cannot convert type to Python. Type is unhandled by capnproto library")
 
-
 cdef toPythonByValue(C_DynamicValue.Builder self, object parent):
     cdef int type = self.getType()
     if type == capnp.TYPE_BOOL:
@@ -309,6 +308,12 @@ cdef toPythonByValue(C_DynamicValue.Builder self, object parent):
     else:
         raise ValueError("Cannot convert type to Python. Type is unhandled by capnproto library")
 
+cdef getWhichReader(C_DynamicValue.Reader & val):
+    return fixMaybe(val.asUnion().which()).getProto().getName().cStr()
+
+cdef getWhichBuilder(C_DynamicValue.Builder & val):
+    return fixMaybe(val.asUnion().which()).getProto().getName().cStr()
+
 cdef class _DynamicStructReader:
     cdef C_DynamicStruct.Reader thisptr
     cdef public object _parent
@@ -326,6 +331,14 @@ cdef class _DynamicStructReader:
     def _has(self, field):
         return self.thisptr.has(field)
 
+    cpdef which(self):
+        try:
+            union = fixMaybeUnion(self.thisptr.getSchema().getUnnamedUnion())
+        except:
+            raise TypeError("This struct has no unnamed enums. You cannot call which on it")
+
+        return getWhichReader(self.thisptr.getByUnion(union))
+
 cdef class _DynamicStructBuilder:
     cdef C_DynamicStruct.Builder thisptr
     cdef public object _parent
@@ -381,6 +394,14 @@ cdef class _DynamicStructBuilder:
         else:
             return toPythonByValue(self.thisptr.init(field, size), self._parent)
 
+    cpdef which(self):
+        try:
+            union = fixMaybeUnion(self.thisptr.getSchema().getUnnamedUnion())
+        except:
+            raise TypeError("This struct has no unnamed enums. You cannot call which on it")
+
+        return getWhichBuilder(self.thisptr.getByUnion(union))
+
 cdef class _DynamicUnionReader:
     cdef C_DynamicUnion.Reader thisptr
     cdef public object _parent
diff --git a/capnp/capnp_cpp.pxd b/capnp/capnp_cpp.pxd
index 7a152b5..c96fa4f 100644
--- a/capnp/capnp_cpp.pxd
+++ b/capnp/capnp_cpp.pxd
@@ -55,6 +55,7 @@ cdef extern from "capnp/schema.h" namespace " ::capnp":
         Node.Reader getProto()
         MemberList getMembers()
         Member getMemberByName(char * name)
+        Maybe[StructSchema.Union] getUnnamedUnion()
 
     cdef cppclass EnumSchema:
         cppclass Enumerant:
@@ -102,16 +103,21 @@ cdef extern from "capnp/dynamic.h" namespace " ::capnp":
     cdef cppclass DynamicStruct:
         cppclass Reader:
             DynamicValueForward.Reader get(char *) except +ValueError
+            DynamicValueForward.Reader getByUnion'get'(StructSchema.Union member) except +ValueError
             bint has(char *) except +ValueError
+            StructSchema getSchema()
         cppclass Builder:
             DynamicValueForward.Builder get(char *) except +ValueError
+            DynamicValueForward.Builder getByUnion'get'(StructSchema.Union member) except +ValueError
             bint has(char *) except +ValueError
             void set(char *, DynamicValueForward.Reader&) except +ValueError
             DynamicValueForward.Builder init(char *, uint size)
             DynamicValueForward.Builder init(char *)
+            StructSchema getSchema()
 
 cdef extern from "fixMaybe.h":
     StructSchema.Member fixMaybe(Maybe[StructSchema.Member]) except+
+    StructSchema.Union fixMaybeUnion'fixMaybe'(Maybe[StructSchema.Union]) except+
     EnumSchema.Enumerant fixMaybe(Maybe[EnumSchema.Enumerant]) except+
 
 cdef extern from "capnp/dynamic.h" namespace " ::capnp":
diff --git a/setup.py b/setup.py
index c671b5a..55700d3 100644
--- a/setup.py
+++ b/setup.py
@@ -70,6 +70,6 @@ setup(
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.2',
         'Programming Language :: Python :: 3.3',
-        'Programming Language :: Python :: Implementation :: PyPy'
+        'Programming Language :: Python :: Implementation :: PyPy',
         'Topic :: Communications'],
 )