diff --git a/libraries/stdlib/src/generated/_Sets.kt b/libraries/stdlib/src/generated/_Sets.kt
new file mode 100644
index 00000000000..961e19e8a9a
--- /dev/null
+++ b/libraries/stdlib/src/generated/_Sets.kt
@@ -0,0 +1,440 @@
+package kotlin
+
+//
+// NOTE THIS FILE IS AUTO-GENERATED by the GenerateStandardLib.kt
+// See: https://github.com/JetBrains/kotlin/tree/master/libraries/stdlib
+//
+
+import java.util.*
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun <T> Array<out T>.distinct(): Set<T> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun BooleanArray.distinct(): Set<Boolean> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun ByteArray.distinct(): Set<Byte> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun CharArray.distinct(): Set<Char> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun DoubleArray.distinct(): Set<Double> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun FloatArray.distinct(): Set<Float> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun IntArray.distinct(): Set<Int> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun LongArray.distinct(): Set<Long> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun ShortArray.distinct(): Set<Short> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from the given collection.
+ */
+public fun <T> Iterable<T>.distinct(): Set<T> {
+    return this.toMutableSet()
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun <T> Array<out T>.intersect(other: Iterable<T>): Set<T> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun BooleanArray.intersect(other: Iterable<Boolean>): Set<Boolean> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun ByteArray.intersect(other: Iterable<Byte>): Set<Byte> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun CharArray.intersect(other: Iterable<Char>): Set<Char> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun DoubleArray.intersect(other: Iterable<Double>): Set<Double> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun FloatArray.intersect(other: Iterable<Float>): Set<Float> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun IntArray.intersect(other: Iterable<Int>): Set<Int> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun LongArray.intersect(other: Iterable<Long>): Set<Long> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun ShortArray.intersect(other: Iterable<Short>): Set<Short> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun <T> Iterable<T>.intersect(other: Iterable<T>): Set<T> {
+    val set = this.toMutableSet()
+    set.retainAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun <T> Array<out T>.subtract(other: Iterable<T>): Set<T> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun BooleanArray.subtract(other: Iterable<Boolean>): Set<Boolean> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun ByteArray.subtract(other: Iterable<Byte>): Set<Byte> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun CharArray.subtract(other: Iterable<Char>): Set<Char> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun DoubleArray.subtract(other: Iterable<Double>): Set<Double> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun FloatArray.subtract(other: Iterable<Float>): Set<Float> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun IntArray.subtract(other: Iterable<Int>): Set<Int> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun LongArray.subtract(other: Iterable<Long>): Set<Long> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun ShortArray.subtract(other: Iterable<Short>): Set<Short> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun <T> Iterable<T>.subtract(other: Iterable<T>): Set<T> {
+    val set = this.toMutableSet()
+    set.removeAll(other)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun <T> Array<out T>.toMutableSet(): MutableSet<T> {
+    val set = LinkedHashSet<T>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun BooleanArray.toMutableSet(): MutableSet<Boolean> {
+    val set = LinkedHashSet<Boolean>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun ByteArray.toMutableSet(): MutableSet<Byte> {
+    val set = LinkedHashSet<Byte>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun CharArray.toMutableSet(): MutableSet<Char> {
+    val set = LinkedHashSet<Char>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun DoubleArray.toMutableSet(): MutableSet<Double> {
+    val set = LinkedHashSet<Double>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun FloatArray.toMutableSet(): MutableSet<Float> {
+    val set = LinkedHashSet<Float>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun IntArray.toMutableSet(): MutableSet<Int> {
+    val set = LinkedHashSet<Int>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun LongArray.toMutableSet(): MutableSet<Long> {
+    val set = LinkedHashSet<Long>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun ShortArray.toMutableSet(): MutableSet<Short> {
+    val set = LinkedHashSet<Short>(size)
+    for (item in this) set.add(item)
+    return set
+}
+
+/**
+ * Returns a mutable set containing all distinct elements from the given collection.
+ */
+public fun <T> Iterable<T>.toMutableSet(): MutableSet<T> {
+    return when (this) {
+        is Collection<T> -> LinkedHashSet(this)
+        else -> toCollection(LinkedHashSet<T>())
+    }
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun <T> Array<out T>.union(other: Iterable<T>): Set<T> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun BooleanArray.union(other: Iterable<Boolean>): Set<Boolean> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun ByteArray.union(other: Iterable<Byte>): Set<Byte> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun CharArray.union(other: Iterable<Char>): Set<Char> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun DoubleArray.union(other: Iterable<Double>): Set<Double> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun FloatArray.union(other: Iterable<Float>): Set<Float> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun IntArray.union(other: Iterable<Int>): Set<Int> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun LongArray.union(other: Iterable<Long>): Set<Long> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun ShortArray.union(other: Iterable<Short>): Set<Short> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
+/**
+ * Returns a set containing all distinct elements from both collections.
+ */
+public fun <T> Iterable<T>.union(other: Iterable<T>): Set<T> {
+    val set = this.toMutableSet()
+    set.addAll(other)
+    return set
+}
+
diff --git a/libraries/stdlib/src/kotlin/collections/MutableCollections.kt b/libraries/stdlib/src/kotlin/collections/MutableCollections.kt
index ba221cfd04c..0aa9191f8d7 100644
--- a/libraries/stdlib/src/kotlin/collections/MutableCollections.kt
+++ b/libraries/stdlib/src/kotlin/collections/MutableCollections.kt
@@ -3,17 +3,64 @@ package kotlin
 /**
  * Adds all elements of the given *iterable* to this [[MutableCollection]]
  */
-public fun <T> MutableCollection<in T>.addAll(iterable: Iterable<T>): Unit {
+public fun <T> MutableCollection<in T>.addAll(iterable: Iterable<T>) {
     when (iterable) {
         is Collection -> addAll(iterable)
-        else -> for (e in iterable) add(e)
+        else -> for (item in iterable) add(item)
     }
 }
 
-public fun <T> MutableCollection<in T>.addAll(stream: Stream<T>): Unit {
-    for (e in stream) add(e)
+/**
+ * Adds all elements of the given *stream* to this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.addAll(stream: Stream<T>) {
+    for (item in stream) add(item)
 }
 
-public fun <T> MutableCollection<in T>.addAll(array: Array<T>): Unit {
-    for (e in array) add(e)
+/**
+ * Adds all elements of the given *array* to this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.addAll(array: Array<T>) {
+    for (item in array) add(item)
+}
+
+/**
+ * Removes all elements of the given *iterable* from this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.removeAll(iterable: Iterable<T>) {
+    when (iterable) {
+        is Collection -> removeAll(iterable)
+        else -> for (item in iterable) remove(item)
+    }
+}
+
+/**
+ * Removes all elements of the given *stream* from this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.removeAll(stream: Stream<T>) {
+    for (item in stream) remove(item)
+}
+
+/**
+ * Removes all elements of the given *array* from this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.removeAll(array: Array<T>) {
+    for (item in array) remove(item)
+}
+
+/**
+ * Retains only elements of the given *iterable* in this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.retainAll(iterable: Iterable<T>) {
+    when (iterable) {
+        is Collection -> retainAll(iterable)
+        else -> retainAll(iterable.toSet())
+    }
+}
+
+/**
+ * Retains only elements of the given *array* in this [[MutableCollection]]
+ */
+public fun <T> MutableCollection<in T>.retainAll(array: Array<T>) {
+    retainAll(array.toSet())
 }
diff --git a/libraries/stdlib/test/collections/SetOperationsTest.kt b/libraries/stdlib/test/collections/SetOperationsTest.kt
new file mode 100644
index 00000000000..6528a3bed34
--- /dev/null
+++ b/libraries/stdlib/test/collections/SetOperationsTest.kt
@@ -0,0 +1,30 @@
+package test.collections
+
+import kotlin.test.*
+import org.junit.Test as test
+
+class SetOperationsTest {
+    test fun distinct() {
+        assertEquals(listOf(1, 3, 5), listOf(1, 3, 3, 1, 5, 1, 3).distinct().toList())
+        assertEquals(listOf<Int>(), listOf<Int>().distinct().toList())
+    }
+
+    test fun union() {
+        assertEquals(listOf(1, 3, 5), listOf(1, 3).union(listOf(5)).toList())
+        assertEquals(listOf(1), listOf<Int>().union(listOf(1)).toList())
+    }
+
+    test fun subtract() {
+        assertEquals(listOf(1, 3), listOf(1, 3).subtract(listOf(5)).toList())
+        assertEquals(listOf(1, 3), listOf(1, 3, 5).subtract(listOf(5)).toList())
+        assertEquals(listOf<Int>(), listOf(1, 3, 5).subtract(listOf(1, 3, 5)).toList())
+        assertEquals(listOf<Int>(), listOf<Int>().subtract(listOf(1)).toList())
+    }
+
+    test fun intersect() {
+        assertEquals(listOf<Int>(), listOf(1, 3).intersect(listOf(5)).toList())
+        assertEquals(listOf(5), listOf(1, 3, 5).intersect(listOf(5)).toList())
+        assertEquals(listOf(1, 3, 5), listOf(1, 3, 5).intersect(listOf(1, 3, 5)).toList())
+        assertEquals(listOf<Int>(), listOf<Int>().intersect(listOf(1)).toList())
+    }
+}
\ No newline at end of file
diff --git a/libraries/tools/kotlin-stdlib-gen/src/generators/GenerateCollections.kt b/libraries/tools/kotlin-stdlib-gen/src/generators/GenerateCollections.kt
index 2e43193bbd4..bc4deb906ad 100644
--- a/libraries/tools/kotlin-stdlib-gen/src/generators/GenerateCollections.kt
+++ b/libraries/tools/kotlin-stdlib-gen/src/generators/GenerateCollections.kt
@@ -12,6 +12,7 @@ fun generateCollectionsAPI(outDir: File) {
     arrays().writeTo(File(outDir, "_Arrays.kt")) { build() }
     snapshots().writeTo(File(outDir, "_Snapshots.kt")) { build() }
     mapping().writeTo(File(outDir, "_Mapping.kt")) { build() }
+    sets().writeTo(File(outDir, "_Sets.kt")) { build() }
     aggregates().writeTo(File(outDir, "_Aggregates.kt")) { build() }
     guards().writeTo(File(outDir, "_Guards.kt")) { build() }
     generators().writeTo(File(outDir, "_Generators.kt")) { build() }
diff --git a/libraries/tools/kotlin-stdlib-gen/src/templates/Sets.kt b/libraries/tools/kotlin-stdlib-gen/src/templates/Sets.kt
new file mode 100644
index 00000000000..6009f4535ec
--- /dev/null
+++ b/libraries/tools/kotlin-stdlib-gen/src/templates/Sets.kt
@@ -0,0 +1,81 @@
+package templates
+
+import templates.Family.*
+
+fun sets(): List<GenericFunction> {
+    val templates = arrayListOf<GenericFunction>()
+
+    templates add f("toMutableSet()") {
+        exclude(Strings, Streams)
+        doc { "Returns a mutable set containing all distinct elements from the given collection." }
+        returns("MutableSet<T>")
+        body {
+            """
+            return when (this) {
+                is Collection<T> -> LinkedHashSet(this)
+                else -> toCollection(LinkedHashSet<T>())
+            }
+            """
+        }
+        body(ArraysOfObjects, ArraysOfPrimitives) {
+            """
+            val set = LinkedHashSet<T>(size)
+            for (item in this) set.add(item)
+            return set
+            """
+        }
+    }
+
+    templates add f("distinct()") {
+        exclude(Strings, Streams)
+        doc { "Returns a set containing all distinct elements from the given collection." }
+
+        returns("Set<T>")
+        body {
+            """
+            return this.toMutableSet()
+            """
+        }
+    }
+
+    templates add f("union(other: Iterable<T>)") {
+        exclude(Strings, Streams)
+        doc { "Returns a set containing all distinct elements from both collections." }
+        returns("Set<T>")
+        body {
+            """
+            val set = this.toMutableSet()
+            set.addAll(other)
+            return set
+            """
+        }
+    }
+
+    templates add f("intersect(other: Iterable<T>)") {
+        exclude(Strings, Streams)
+        doc { "Returns a set containing all distinct elements from both collections." }
+        returns("Set<T>")
+        body {
+            """
+            val set = this.toMutableSet()
+            set.retainAll(other)
+            return set
+            """
+        }
+    }
+
+    templates add f("subtract(other: Iterable<T>)") {
+        exclude(Strings, Streams)
+        doc { "Returns a set containing all distinct elements from both collections." }
+        returns("Set<T>")
+        body {
+            """
+            val set = this.toMutableSet()
+            set.removeAll(other)
+            return set
+            """
+        }
+    }
+
+    return templates
+}
\ No newline at end of file