diff --git a/CHANGELOG b/CHANGELOG
index a371186..903a16a 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -2,6 +2,7 @@
 - Removed encoding from .desktop file (was deprecated)
 - Added manpage for relational-cli
 - Internally uses set instead of lists to describe relation's content
+- Tuples are internally mapped on tuples and no longer on lists
 - Discards the old and not so functional tlb format
 - Rename will mark the resulting relation as readonly and subsequent updates, insert or deletes will actually copy the content
 
diff --git a/relational/relation.py b/relational/relation.py
index d623ff9..854f39a 100644
--- a/relational/relation.py
+++ b/relational/relation.py
@@ -381,16 +381,13 @@ class relation (object):
     def __eq__(self,other):
         '''Returns true if the relations are the same, ignoring order of items.
         This operation is rather heavy, since it requires sorting and comparing.'''
-        other=self._rearrange_(other) #Rearranges attributes' order so can compare tuples directly
         if (self.__class__!=other.__class__)or(self.header!=other.header):
             return False #Both parameters must be a relation
+
+        if set(self.header.attributes)!=set(other.header.attributes):
+            return False
         
-        #Comparing header
-        if len(self.header.attributes) != len(other.header.attributes):
-            return False #Not the same number of attributes -> not equals
-        for i in self.header.attributes:
-            if i not in other.header.attributes:
-                return False #Non shared attribute
+        other=self._rearrange_(other) #Rearranges attributes' order so can compare tuples directly
         
         #comparing content
         return self.content==other.content