diff --git a/python/resources/inspectionDescriptions/PyRedeclarationInspection.html b/python/resources/inspectionDescriptions/PyRedeclarationInspection.html
index 0175bc40b6a6..7ef9296a01d2 100644
--- a/python/resources/inspectionDescriptions/PyRedeclarationInspection.html
+++ b/python/resources/inspectionDescriptions/PyRedeclarationInspection.html
@@ -5,6 +5,5 @@ This inspection detects redeclarations of names without being used in between, l
 x = 2
 </pre>
 It applies to function and class declarations, and assignments.<br/>
-<i>Currently it works in a very limited way and is off by default.</i>
 </span></body>
 </html>
diff --git a/python/src/META-INF/python-plugin-core.xml b/python/src/META-INF/python-plugin-core.xml
index 681304de2d11..85f2357002d1 100644
--- a/python/src/META-INF/python-plugin-core.xml
+++ b/python/src/META-INF/python-plugin-core.xml
@@ -260,7 +260,7 @@
     <stubElementTypeHolder class="com.jetbrains.python.PyElementTypes"/>
 
     <localInspection language="Python" shortName="PyArgumentListInspection" bundle="com.jetbrains.python.PyBundle" key="INSP.NAME.incorrect.call.arguments" groupKey="INSP.GROUP.python" enabledByDefault="true"  level="WARNING" implementationClass="com.jetbrains.python.inspections.PyArgumentListInspection"/>
-    <localInspection language="Python" shortName="PyRedeclarationInspection" bundle="com.jetbrains.python.PyBundle" key="INSP.NAME.redeclaration" groupKey="INSP.GROUP.python" enabledByDefault="false"  level="WARNING" implementationClass="com.jetbrains.python.inspections.PyRedeclarationInspection"/>
+    <localInspection language="Python" shortName="PyRedeclarationInspection" bundle="com.jetbrains.python.PyBundle" key="INSP.NAME.redeclaration" groupKey="INSP.GROUP.python" enabledByDefault="true"  level="WARNING" implementationClass="com.jetbrains.python.inspections.PyRedeclarationInspection"/>
     <localInspection language="Python" shortName="PyUnresolvedReferencesInspection" bundle="com.jetbrains.python.PyBundle" key="INSP.NAME.unresolved.refs" groupKey="INSP.GROUP.python" enabledByDefault="true"  level="WARNING" implementationClass="com.jetbrains.python.inspections.PyUnresolvedReferencesInspection"/>
     <localInspection language="Python" shortName="PyInterpreterInspection" bundle="com.jetbrains.python.PyBundle" key="INSP.NAME.invalid.interpreter" groupKey="INSP.GROUP.python" enabledByDefault="true"  level="WARNING" implementationClass="com.jetbrains.python.inspections.PyInterpreterInspection"/>
     <localInspection language="Python" shortName="PyMethodParametersInspection" bundle="com.jetbrains.python.PyBundle" key="INSP.NAME.problematic.first.parameter" groupKey="INSP.GROUP.python" enabledByDefault="true"  level="WEAK WARNING" implementationClass="com.jetbrains.python.inspections.PyMethodParametersInspection"/>
diff --git a/python/src/com/jetbrains/python/PyBundle.properties b/python/src/com/jetbrains/python/PyBundle.properties
index 454067904cdc..6d9d5854c1c0 100644
--- a/python/src/com/jetbrains/python/PyBundle.properties
+++ b/python/src/com/jetbrains/python/PyBundle.properties
@@ -280,7 +280,7 @@ INSP.decorator.receives.unexpected.builtin=This decorator will not receive a cal
 
 # PyRedeclarationInspection
 INSP.NAME.redeclaration=Names redeclared without usage
-INSP.shadows.same.named.$0.above=Shadows same-named {0} above
+INSP.shadows.same.named.$0.above=Shadows a {0} with the same name defined above
 
 # PyUnresolvedReferencesInspection
 INSP.NAME.unresolved.refs=Unresolved references
diff --git a/python/src/com/jetbrains/python/inspections/PyRedeclarationInspection.java b/python/src/com/jetbrains/python/inspections/PyRedeclarationInspection.java
index e566674c8e54..77df179260a8 100644
--- a/python/src/com/jetbrains/python/inspections/PyRedeclarationInspection.java
+++ b/python/src/com/jetbrains/python/inspections/PyRedeclarationInspection.java
@@ -1,27 +1,30 @@
 package com.jetbrains.python.inspections;
 
+import com.intellij.codeInsight.controlflow.ControlFlowUtil;
+import com.intellij.codeInsight.controlflow.Instruction;
 import com.intellij.codeInspection.LocalInspectionToolSession;
 import com.intellij.codeInspection.ProblemsHolder;
-import com.intellij.lang.ASTNode;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiElementVisitor;
+import com.intellij.psi.PsiNameIdentifierOwner;
+import com.intellij.util.Function;
 import com.jetbrains.python.PyBundle;
-import com.jetbrains.python.PyTokenTypes;
-import com.jetbrains.python.psi.PyClass;
-import com.jetbrains.python.psi.PyElement;
-import com.jetbrains.python.psi.PyFunction;
-import com.jetbrains.python.psi.PyTargetExpression;
-import com.jetbrains.python.psi.resolve.PyResolveUtil;
-import com.jetbrains.python.psi.resolve.ResolveProcessor;
+import com.jetbrains.python.codeInsight.controlflow.ControlFlowCache;
+import com.jetbrains.python.codeInsight.controlflow.ReadWriteInstruction;
+import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
+import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
+import com.jetbrains.python.psi.*;
 import org.jetbrains.annotations.Nls;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 /**
- * Annotates declarations that unconditionally ovverride other without these being used.
- * E.g.: <code>x = 1; x = 2</code>
- * User: dcheryasov
- * Date: Nov 14, 2008
+ * Annotates declarations that unconditionally override others without these being used.
+ *
+ * @author dcheryasov
+ * @author vlan
+ *
+ * TODO: Add a rename quick-fix
  */
 public class PyRedeclarationInspection extends PyInspection {
   @Nls
@@ -30,10 +33,6 @@ public class PyRedeclarationInspection extends PyInspection {
     return PyBundle.message("INSP.NAME.redeclaration");
   }
 
-  @Override
-  public boolean isEnabledByDefault() {
-    return false; // too immature yet
-  }
 
   @NotNull
   @Override
@@ -43,54 +42,83 @@ public class PyRedeclarationInspection extends PyInspection {
     return new Visitor(holder, session);
   }
 
-  public static class Visitor extends PyInspectionVisitor {
+  private static class Visitor extends PyInspectionVisitor {
     public Visitor(@Nullable ProblemsHolder holder, @NotNull LocalInspectionToolSession session) {
       super(holder, session);
     }
 
-    // TODO: This function is a shame; replace with a proper interface.
-    private static String _getKind(PsiElement elt) {
-      if (elt instanceof PyFunction) return PyBundle.message("GNAME.function");
-      if (elt instanceof PyClass) return PyBundle.message("GNAME.class");
-      if (elt instanceof PyTargetExpression) return PyBundle.message("GNAME.var");
-      return PyBundle.message("GNAME.item");
-    }
-
-    private void _checkAbove(PyElement node) {
-      String name = node.getName();
-      if (name != null) {
-        ResolveProcessor proc = new ResolveProcessor(node.getName());
-        PyResolveUtil.treeCrawlUp(proc, node);
-        PsiElement found = proc.getResult();
-        // TODO: check if the redefined name is used somehow
-        if (found != null && ! (found instanceof PyTargetExpression)) {
-          final ASTNode identifier = node.getNode().findChildByType(PyTokenTypes.IDENTIFIER);
-          if (identifier != null) {
-            registerProblem(
-              identifier.getPsi(),
-              PyBundle.message("INSP.shadows.same.named.$0.above", _getKind(found))
-            );
-          }
-          //registerProblem(prev.getNode().findChildByType(PyTokenTypes.IDENTIFIER).getPsi(), "Overridden by same-named " + kind + " below");
-        }
-      }
-    }
-
-    // TODO: add a rename quickfix
-
     @Override
     public void visitPyFunction(final PyFunction node) {
-      _checkAbove(node);
+      if (!isDecorated(node)) {
+        processElement(node);
+      }
     }
 
     @Override
     public void visitPyTargetExpression(final PyTargetExpression node) {
-      _checkAbove(node);
+      final ScopeOwner owner = ScopeUtil.getScopeOwner(node);
+      if (owner instanceof PyFile || owner instanceof PyClass) {
+        processElement(node);
+      }
     }
 
     @Override
     public void visitPyClass(final PyClass node) {
-      _checkAbove(node);
+      if (!isDecorated(node)) {
+        processElement(node);
+      }
+    }
+
+    private static boolean isDecorated(@NotNull PyDecoratable node) {
+      boolean isDecorated = false;
+      final PyDecoratorList decoratorList = node.getDecoratorList();
+      if (decoratorList != null) {
+        final PyDecorator[] decorators = decoratorList.getDecorators();
+        if (decorators.length > 0) {
+          isDecorated = true;
+        }
+      }
+      return isDecorated;
+    }
+
+    private void processElement(@NotNull final PsiNameIdentifierOwner element) {
+      final String name = element.getName();
+      final ScopeOwner owner = ScopeUtil.getScopeOwner(element);
+      if (owner != null && name != null) {
+        final Instruction[] instructions = ControlFlowCache.getControlFlow(owner).getInstructions();
+        final int startInstruction = ControlFlowUtil.findInstructionNumberByElement(instructions, element);
+        ControlFlowUtil.iteratePrev(startInstruction, instructions, new Function<Instruction, ControlFlowUtil.Operation>() {
+          @Override
+          public ControlFlowUtil.Operation fun(Instruction instruction) {
+            if (instruction instanceof ReadWriteInstruction && instruction.num() != startInstruction) {
+              final ReadWriteInstruction rwInstruction = (ReadWriteInstruction)instruction;
+              if (name.equals(rwInstruction.getName())) {
+                if (rwInstruction.getAccess().isWriteAccess()) {
+                  final PsiElement shadowed = rwInstruction.getElement();
+                  final PsiElement identifier = element.getNameIdentifier();
+                  registerProblem(identifier != null ? identifier : element,
+                                  PyBundle.message("INSP.shadows.same.named.$0.above", getKind(shadowed)));
+                }
+                return ControlFlowUtil.Operation.BREAK;
+              }
+            }
+            return ControlFlowUtil.Operation.NEXT;
+          }
+        });
+      }
+    }
+  }
+
+  @NotNull
+  private static String getKind(@Nullable PsiElement element) {
+    if (element instanceof PyFunction) {
+      return PyBundle.message("GNAME.function");
+    }
+    else if (element instanceof PyClass) {
+      return PyBundle.message("GNAME.class");
+    }
+    else {
+      return PyBundle.message("GNAME.var");
     }
   }
 }
diff --git a/python/testData/inspections/PyRedeclarationInspection/expected.xml b/python/testData/inspections/PyRedeclarationInspection/expected.xml
index 3adaf3cadd08..538b4a439a17 100644
--- a/python/testData/inspections/PyRedeclarationInspection/expected.xml
+++ b/python/testData/inspections/PyRedeclarationInspection/expected.xml
@@ -3,23 +3,21 @@
   <problem>
     <file>dupes.py</file>
     <line>2</line>
-    <description>Shadows same-named class above</description>
+    <description>Shadows a class with the same name defined above</description>
   </problem>
   <problem>
     <file>dupes.py</file>
     <line>5</line>
-    <description>Shadows same-named function above</description>
+    <description>Shadows a function with the same name defined above</description>
   </problem>
   <problem>
     <file>dupes.py</file>
     <line>8</line>
-    <description>Shadows same-named function above</description>
+    <description>Shadows a function with the same name defined above</description>
   </problem>
-  <!--
   <problem>
     <file>dupes.py</file>
     <line>9</line>
-    <description>Shadows same-named variable above</description>
+    <description>Shadows a variable with the same name defined above</description>
   </problem>
-  -->
 </problems>