Index: src/OFMutableSet.h
==================================================================
--- src/OFMutableSet.h
+++ src/OFMutableSet.h
@@ -29,10 +29,28 @@
 # ifndef DOXYGEN
 #  define ObjectType id
 # endif
 @interface OFMutableSet: OFSet
 #endif
+/*!
+ * @brief Creates a new OFMutableSet with enough memory to hold the specified
+ *	  number of objects.
+ *
+ * @param capacity The initial capacity for the OFMutableSet
+ * @return A new autoreleased OFMutableSet
+ */
++ (instancetype)setWithCapacity: (size_t)capacity;
+
+/*!
+ * @brief Initializes an already allocated OFMutableSet with enough memory to
+ *	  hold the specified number of objects.
+ *
+ * @param capacity The initial capacity for the OFMutableSet
+ * @return An initialized OFMutableSet
+ */
+- initWithCapacity: (size_t)capacity;
+
 /*!
  * @brief Adds the specified object to the set.
  *
  * @param object The object to add to the set
  */

Index: src/OFMutableSet.m
==================================================================
--- src/OFMutableSet.m
+++ src/OFMutableSet.m
@@ -76,10 +76,15 @@
 - initWithSerialization: (OFXMLElement*)element
 {
 	return (id)[[OFMutableSet_hashtable alloc]
 	    initWithSerialization: element];
 }
+
+- initWithCapacity: (size_t)capacity
+{
+	return (id)[[OFMutableSet_hashtable alloc] initWithCapacity: capacity];
+}
 
 - retain
 {
 	return self;
 }
@@ -114,10 +119,15 @@
 	if (self == [OFMutableSet class])
 		return (id)&placeholder;
 
 	return [super alloc];
 }
+
++ (instancetype)setWithCapacity: (size_t)capacity
+{
+	return [[[self alloc] initWithCapacity: capacity] autorelease];
+}
 
 - init
 {
 	if (object_getClass(self) == [OFMutableSet class]) {
 		@try {
@@ -129,10 +139,15 @@
 		}
 	}
 
 	return [super init];
 }
+
+- initWithCapacity: (size_t)capacity
+{
+	OF_INVALID_INIT_METHOD
+}
 
 - (void)addObject: (id)object
 {
 	OF_UNRECOGNIZED_SELECTOR
 }