Index: src/OFDataArray.h
==================================================================
--- src/OFDataArray.h
+++ src/OFDataArray.h
@@ -88,19 +88,39 @@
  *
  * \param item A pointer to an arbitrary item
  */
 - addItem: (void*)item;
 
+/**
+ * Adds an item to the OFDataArray at the specified index.
+ *
+ * \param item A pointer to an arbitrary item
+ * \param index The index where the item should be added
+ */
+- addItem: (void*)item
+  atIndex: (size_t)index;
+
 /**
  * Adds items from a C array to the OFDataArray.
  *
  * \param nitems The number of items to add
  * \param carray A C array containing the items to add
  */
 -  addNItems: (size_t)nitems
   fromCArray: (void*)carray;
 
+/**
+ * Adds items from a C array to the OFDataArray at the specified index.
+ *
+ * \param nitems The number of items to add
+ * \param carray A C array containing the items to add
+ * \param index The index where the items should be added
+ */
+-  addNItems: (size_t)nitems
+  fromCArray: (void*)carray
+     atIndex: (size_t)index;
+
 /**
  * Removes the item at the specified index.
  *
  * \param index The index of the item to remove
  */

Index: src/OFDataArray.m
==================================================================
--- src/OFDataArray.m
+++ src/OFDataArray.m
@@ -103,14 +103,24 @@
 
 	data = [self resizeMemory: data
 			 toNItems: count + 1
 			 withSize: itemsize];
 
-	memcpy(data + count++ * itemsize, item, itemsize);
+	memcpy(data + count * itemsize, item, itemsize);
+
+	count++;
 
 	return self;
 }
+
+- addItem: (void*)item
+  atIndex: (size_t)index
+{
+	return [self addNItems: 1
+		    fromCArray: item
+		       atIndex: index];
+}
 
 -  addNItems: (size_t)nitems
   fromCArray: (void*)carray
 {
 	if (nitems > SIZE_MAX - count)
@@ -119,10 +129,30 @@
 	data = [self resizeMemory: data
 			 toNItems: count + nitems
 			 withSize: itemsize];
 
 	memcpy(data + count * itemsize, carray, nitems * itemsize);
+	count += nitems;
+
+	return self;
+}
+
+- addNItems: (size_t)nitems
+ fromCArray: (void*)carray
+    atIndex: (size_t)index
+{
+	if (nitems > SIZE_MAX - count)
+		@throw [OFOutOfRangeException newWithClass: isa];
+
+	data = [self resizeMemory: data
+			 toNItems: count + nitems
+			 withSize: itemsize];
+
+	memmove(data + (index + nitems) * itemsize, data + index * itemsize,
+	    (count - index) * itemsize);
+	memcpy(data + index * itemsize, carray, nitems * itemsize);
+
 	count += nitems;
 
 	return self;
 }
 
@@ -268,11 +298,13 @@
 
 	if (size != nsize)
 		data = [self resizeMemory: data
 				   toSize: nsize];
 
-	memcpy(data + count++ * itemsize, item, itemsize);
+	memcpy(data + count * itemsize, item, itemsize);
+
+	count++;
 	size = nsize;
 
 	return self;
 }
 
@@ -289,10 +321,37 @@
 	if (size != nsize)
 		data = [self resizeMemory: data
 				   toSize: nsize];
 
 	memcpy(data + count * itemsize, carray, nitems * itemsize);
+
+	count += nitems;
+	size = nsize;
+
+	return self;
+}
+
+- addNItems: (size_t)nitems
+ fromCArray: (void*)carray
+    atIndex: (size_t)index
+{
+	size_t nsize;
+
+	if (nitems > SIZE_MAX - count || count + nitems > SIZE_MAX / itemsize)
+		@throw [OFOutOfRangeException newWithClass: isa];
+
+	nsize = ((count + nitems) * itemsize + lastpagebyte) & ~lastpagebyte;
+
+	if (size != nsize)
+		data = [self resizeMemory: data
+				 toNItems: nsize
+				 withSize: itemsize];
+
+	memmove(data + (index + nitems) * itemsize, data + index * itemsize,
+	    (count - index) * itemsize);
+	memcpy(data + index * itemsize, carray, nitems * itemsize);
+
 	count += nitems;
 	size = nsize;
 
 	return self;
 }

Index: tests/OFDataArray.m
==================================================================
--- tests/OFDataArray.m
+++ tests/OFDataArray.m
@@ -84,11 +84,16 @@
 
 	TEST(@"-[removeNItems:atIndex:]",
 	    [array[0] removeNItems: 2
 			   atIndex: 1] && [array[0] count] == 3 &&
 	    !memcmp([array[0] cArray], "ade", 3))
-	[array[0] addItem: ""];
+
+	TEST(@"-[addNItems:atIndex:]",
+	    [array[0] addNItems: 2
+		     fromCArray: "bc"
+			atIndex: 1] && [array[0] count] == 5 &&
+	    !memcmp([array[0] cArray], "abcde", 5))
 
 	TEST(@"Building strings",
 	    (array[0] = [class dataArrayWithItemSize: 1]) &&
 	    [array[0] addNItems: 6
 		     fromCArray: (void*)str] && [array[0] addItem: ""] &&