diff --git a/heaps/heap_sort.py b/heaps/heap_sort.py
index 3b834a5..c675140 100644
--- a/heaps/heap_sort.py
+++ b/heaps/heap_sort.py
@@ -1,8 +1,17 @@
-
+from heaps.min_heap import MinHeap
 
 def heap_sort(list):
     """ This method uses a heap to sort an array.
-        Time Complexity:  ?
-        Space Complexity: ?
+        Time Complexity:  O(n log n)
+        Space Complexity: O(n)
     """
-    pass
\ No newline at end of file
+    min_heap = MinHeap()
+
+    
+    for element in list:
+        min_heap.add(element)
+
+    for i in range(len(list)):
+        list[i] = min_heap.remove()
+
+    return list
\ No newline at end of file
diff --git a/heaps/min_heap.py b/heaps/min_heap.py
index f6fe4e0..d513968 100644
--- a/heaps/min_heap.py
+++ b/heaps/min_heap.py
@@ -19,10 +19,14 @@ def __init__(self):
     def add(self, key, value = None):
         """ This method adds a HeapNode instance to the heap
             If value == None the new node's value should be set to key
-            Time Complexity: ?
-            Space Complexity: ?
+            Time Complexity: O(log n)
+            Space Complexity: O(log n)
         """
-        pass
+        if value == None:
+            value = key
+
+        self.store.append(HeapNode(key,value))
+        self.heap_up(len(self.store)-1)
 
     def remove(self):
         """ This method removes and returns an element from the heap
@@ -30,7 +34,15 @@ def remove(self):
             Time Complexity: ?
             Space Complexity: ?
         """
-        pass
+        if self.empty():
+            return None
+
+        self.swap(0, len(self.store)-1)
+        min_node = self.store.pop()
+        self.heap_down(0)
+
+        # return str(min_node)
+        return min_node.value
 
 
     
@@ -44,10 +56,11 @@ def __str__(self):
 
     def empty(self):
         """ This method returns true if the heap is empty
-            Time complexity: ?
-            Space complexity: ?
+            Time complexity: O(1)
+            Space complexity: O(1)
         """
-        pass
+        # return self.size() == 0
+        return len(self.store) == 0
 
 
     def heap_up(self, index):
@@ -57,10 +70,15 @@ def heap_up(self, index):
             property is reestablished.
             
             This could be **very** helpful for the add method.
-            Time complexity: ?
-            Space complexity: ?
+            Time complexity: O(log n)
+            Space complexity: O(1)
         """
-        pass
+        parent_node = (index-1) // 2
+
+        if index:
+            if self.store[index].key < self.store[parent_node].key:
+                self.swap(index, parent_node)
+                self.heap_up(parent_node)
 
     def heap_down(self, index):
         """ This helper method takes an index and 
@@ -68,7 +86,20 @@ def heap_down(self, index):
             larger than either of its children and continues until
             the heap property is reestablished.
         """
-        pass
+        left_child = 2 * index + 1
+        right_child = 2 * index + 2
+        if left_child < len(self.store):
+            # if right_child >= len(self.store):
+            #     min_child = left_child
+            # elif self.store[left_child].key < self.store[right_child].key:
+            if right_child >= len(self.store) or self.store[left_child].key < self.store[right_child].key:
+                min_child = left_child
+            else:
+                min_child = right_child
+            
+            if self.store[index].key > self.store[min_child].key:
+                self.swap(index, min_child)
+                self.heap_down(min_child)
 
     
     def swap(self, index_1, index_2):