diff --git a/src/operations/sync/as-indexed-pairs.ts b/src/operations/sync/as-indexed-pairs.ts
deleted file mode 100644
index f8e2fbf..0000000
--- a/src/operations/sync/as-indexed-pairs.ts
+++ /dev/null
@@ -1,22 +0,0 @@
-import { isAsyncIterable, isIterable } from "../../async-like";
-import * as Async from "../async";
-import { Arguments, AsyncFn, GetAsync, Name, SyncOperation } from "../operation";
-
-export function asIndexedPairs<T>() {
-  const fn: SyncOperation<T, Iterable<[number, T]>> = function *asIndexedPairs<T>(iterable: Iterable<T>): Iterable<[number, T]> {
-    if (isAsyncIterable(iterable) && !isIterable(iterable)) throw new Async.ExpectedAsyncOperationError(
-      fn[GetAsync]()
-    );
-    let index = -1;
-    for (const value of iterable) {
-      index += 1;
-      yield [index, value];
-    }
-  };
-  fn[Name] = "asIndexedPairs";
-  fn[Arguments] = [];
-  fn[GetAsync] = () => Async.asIndexedPairs<T>();
-  return fn;
-}
-asIndexedPairs[Name] = "asIndexedPairs";
-asIndexedPairs[AsyncFn] = Async.asIndexedPairs;
diff --git a/src/operations/sync/index.ts b/src/operations/sync/index.ts
index 176a0cb..fcb63ac 100644
--- a/src/operations/sync/index.ts
+++ b/src/operations/sync/index.ts
@@ -16,5 +16,4 @@ export * from "./peek";
 export * from "./take-minimum";
 export * from "./take";
 export * from "./drop";
-export * from "./as-indexed-pairs";
 export * from "./find";
diff --git a/src/tests/tc39/async.ts b/src/tests/tc39/async.ts
index 7239a59..7df7e59 100644
--- a/src/tests/tc39/async.ts
+++ b/src/tests/tc39/async.ts
@@ -1,5 +1,4 @@
 import {
-  asIndexedPairs,
   drop,
   every,
   filter,
@@ -24,7 +23,6 @@ export interface TC39AsyncIterableHelpersObject<T> extends AsyncIterable<T> {
   filter?(filterFn: FilterFn<T>): TC39AsyncIterableHelpersObject<T>;
   take?(limit: number): TC39AsyncIterableHelpersObject<T>;
   drop?(limit: number): TC39AsyncIterableHelpersObject<T>;
-  asIndexedPairs?(): TC39AsyncIterableHelpersObject<[number, T]>;
   flatMap?<O>(mapperFn: MapFn<T, Iterable<O>>): TC39AsyncIterableHelpersObject<O>;
   reduce?<A>(reduceFn: ReduceFn<T, A>, initial: A): Promise<A>;
   toArray?(): Promise<T[]>;
@@ -92,21 +90,6 @@ export async function assertTC39AsyncIteratorHelpersObject<O extends InputOperat
     ok((await dropNaturalsResultIterator.next()).value === 4); //  {value: 4, done: false};
     ok((await dropNaturalsResultIterator.next()).value === 5); //  {value: 5, done: false};
 
-    const asIndexedPairsOps = test(asIndexedPairs());
-    const asIndexedPairsResultIterator = asIndexedPairsOps.instance(["a", "b", "c"])[Symbol.asyncIterator]();
-    const asIndexedPairsResult0 = await asIndexedPairsResultIterator.next();
-    ok(Array.isArray(asIndexedPairsResult0.value));
-    ok(asIndexedPairsResult0.value[0] === 0);
-    ok(asIndexedPairsResult0.value[1] === "a");
-    const asIndexedPairsResult1 = await asIndexedPairsResultIterator.next();
-    ok(Array.isArray(asIndexedPairsResult1.value));
-    ok(asIndexedPairsResult1.value[0] === 1);
-    ok(asIndexedPairsResult1.value[1] === "b");
-    const asIndexedPairsResult2 = await asIndexedPairsResultIterator.next();
-    ok(Array.isArray(asIndexedPairsResult2.value));
-    ok(asIndexedPairsResult2.value[0] === 2);
-    ok(asIndexedPairsResult2.value[1] === "c");
-
     const flatMapOps = test(flatMap((value: string) => value.split(" ")));
     const flatMapResultIterator = flatMapOps.instance(["It's Sunny in", "", "California"])[Symbol.asyncIterator]();
     ok((await flatMapResultIterator.next()).value === "It's"); //  {value: "It's", done: false};
diff --git a/src/tests/tc39/sync.ts b/src/tests/tc39/sync.ts
index d41c237..c4f6b97 100644
--- a/src/tests/tc39/sync.ts
+++ b/src/tests/tc39/sync.ts
@@ -1,11 +1,9 @@
 import {
   InputOperationsArray,
-  isIterableEngineContext,
   IterableEngineContext,
   UnknownReturnedIterableError
 } from "../../engine/context";
 import {
-  asIndexedPairs,
   drop, every,
   filter, FilterFn, find,
   flatMap,
@@ -24,7 +22,6 @@ export interface TC39IterableHelpersObject<T> extends Iterable<T> {
   filter?(filterFn: FilterFn<T>): TC39IterableHelpersObject<T>;
   take?(limit: number): TC39IterableHelpersObject<T>;
   drop?(limit: number): TC39IterableHelpersObject<T>;
-  asIndexedPairs?(): TC39IterableHelpersObject<[number, T]>;
   flatMap?<O>(mapperFn: MapFn<T, Iterable<O>>): TC39IterableHelpersObject<O>;
   reduce?<A>(reduceFn: ReduceFn<T, A>, initial: A): A;
   toArray?(): T[];
@@ -83,19 +80,6 @@ export function assertTC39IteratorHelpersObject<O extends InputOperationsArray,
   ok(dropNaturalsResultIterator.next().value === 4); //  {value: 4, done: false};
   ok(dropNaturalsResultIterator.next().value === 5); //  {value: 5, done: false};
 
-  const asIndexedPairsOps = test(asIndexedPairs());
-  const asIndexedPairsResult = [...asIndexedPairsOps.instance(["a", "b", "c"])];
-  ok(asIndexedPairsResult.length === 3);
-  ok(Array.isArray(asIndexedPairsResult[0]));
-  ok(asIndexedPairsResult[0][0] === 0);
-  ok(asIndexedPairsResult[0][1] === "a");
-  ok(Array.isArray(asIndexedPairsResult[1]));
-  ok(asIndexedPairsResult[1][0] === 1);
-  ok(asIndexedPairsResult[1][1] === "b");
-  ok(Array.isArray(asIndexedPairsResult[2]));
-  ok(asIndexedPairsResult[2][0] === 2);
-  ok(asIndexedPairsResult[2][1] === "c");
-
   const flatMapOps = test(flatMap((value: string) => value.split(" ")));
   const flatMapResultIterator = flatMapOps.instance(["It's Sunny in", "", "California"])[Symbol.iterator]();
   ok(flatMapResultIterator.next().value === "It's"); //  {value: "It's", done: false};