diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java
index cf1be3eb3826..26ee155ea599 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java
@@ -17,6 +17,7 @@
 package com.google.cloud.firestore;
 
 import com.google.api.core.ApiFuture;
+import com.google.api.gax.rpc.ApiStreamObserver;
 import com.google.cloud.Service;
 import java.util.List;
 import javax.annotation.Nonnull;
@@ -117,6 +118,20 @@ <T> ApiFuture<T> runTransaction(
   ApiFuture<List<DocumentSnapshot>> getAll(
       @Nonnull DocumentReference[] documentReferences, @Nullable FieldMask fieldMask);
 
+  /**
+   * Retrieves multiple documents from Firestore while optionally applying a field mask to reduce
+   * the amount of data transmitted. Returned documents will be out of order.
+   *
+   * @param documentReferences Array with Document References to fetch.
+   * @param fieldMask If not null, specifies the subset of fields to return.
+   * @param responseObserver The observer to be notified when {@link DocumentSnapshot} details
+   *     arrive.
+   */
+  void getAll(
+      @Nonnull DocumentReference[] documentReferences,
+      @Nullable FieldMask fieldMask,
+      final ApiStreamObserver<DocumentSnapshot> responseObserver);
+
   /**
    * Gets a Firestore {@link WriteBatch} instance that can be used to combine multiple writes.
    *
diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/FirestoreImpl.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/FirestoreImpl.java
index 77a29901c995..cf9bfdb483c8 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/FirestoreImpl.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/FirestoreImpl.java
@@ -140,23 +140,30 @@ public Iterable<CollectionReference> getCollections() {
   @Override
   public ApiFuture<List<DocumentSnapshot>> getAll(
       @Nonnull DocumentReference... documentReferences) {
-    return this.getAll(documentReferences, null, null);
+    return this.getAll(documentReferences, null, (ByteString) null);
   }
 
   @Nonnull
   @Override
   public ApiFuture<List<DocumentSnapshot>> getAll(
       @Nonnull DocumentReference[] documentReferences, @Nullable FieldMask fieldMask) {
-    return this.getAll(documentReferences, fieldMask, null);
+    return this.getAll(documentReferences, fieldMask, (ByteString) null);
   }
 
-  /** Internal getAll() method that accepts an optional transaction id. */
-  ApiFuture<List<DocumentSnapshot>> getAll(
-      final DocumentReference[] documentReferences,
+  @Nonnull
+  @Override
+  public void getAll(
+      final @Nonnull DocumentReference[] documentReferences,
       @Nullable FieldMask fieldMask,
-      @Nullable ByteString transactionId) {
-    final SettableApiFuture<List<DocumentSnapshot>> futureList = SettableApiFuture.create();
-    final Map<DocumentReference, DocumentSnapshot> resultMap = new HashMap<>();
+      @Nonnull final ApiStreamObserver<DocumentSnapshot> apiStreamObserver) {
+    this.getAll(documentReferences, fieldMask, null, apiStreamObserver);
+  }
+
+  void getAll(
+      final @Nonnull DocumentReference[] documentReferences,
+      @Nullable FieldMask fieldMask,
+      @Nullable ByteString transactionId,
+      final ApiStreamObserver<DocumentSnapshot> apiStreamObserver) {
 
     ApiStreamObserver<BatchGetDocumentsResponse> responseObserver =
         new ApiStreamObserver<BatchGetDocumentsResponse>() {
@@ -176,9 +183,6 @@ public void onNext(BatchGetDocumentsResponse response) {
 
             switch (response.getResultCase()) {
               case FOUND:
-                documentReference =
-                    new DocumentReference(
-                        FirestoreImpl.this, ResourcePath.create(response.getFound().getName()));
                 documentSnapshot =
                     DocumentSnapshot.fromDocument(
                         FirestoreImpl.this,
@@ -198,26 +202,19 @@ public void onNext(BatchGetDocumentsResponse response) {
               default:
                 return;
             }
-
-            resultMap.put(documentReference, documentSnapshot);
+            apiStreamObserver.onNext(documentSnapshot);
           }
 
           @Override
           public void onError(Throwable throwable) {
             tracer.getCurrentSpan().addAnnotation("Firestore.BatchGet: Error");
-            futureList.setException(throwable);
+            apiStreamObserver.onError(throwable);
           }
 
           @Override
           public void onCompleted() {
             tracer.getCurrentSpan().addAnnotation("Firestore.BatchGet: Complete");
-            List<DocumentSnapshot> documentSnapshots = new ArrayList<>();
-
-            for (DocumentReference documentReference : documentReferences) {
-              documentSnapshots.add(resultMap.get(documentReference));
-            }
-
-            futureList.set(documentSnapshots);
+            apiStreamObserver.onCompleted();
           }
         };
 
@@ -244,7 +241,39 @@ public void onCompleted() {
                 "numDocuments", AttributeValue.longAttributeValue(documentReferences.length)));
 
     streamRequest(request.build(), responseObserver, firestoreClient.batchGetDocumentsCallable());
+  }
 
+  /** Internal getAll() method that accepts an optional transaction id. */
+  ApiFuture<List<DocumentSnapshot>> getAll(
+      final @Nonnull DocumentReference[] documentReferences,
+      @Nullable FieldMask fieldMask,
+      @Nullable ByteString transactionId) {
+    final SettableApiFuture<List<DocumentSnapshot>> futureList = SettableApiFuture.create();
+    final Map<DocumentReference, DocumentSnapshot> documentSnapshotMap = new HashMap<>();
+    getAll(
+        documentReferences,
+        fieldMask,
+        transactionId,
+        new ApiStreamObserver<DocumentSnapshot>() {
+          @Override
+          public void onNext(DocumentSnapshot documentSnapshot) {
+            documentSnapshotMap.put(documentSnapshot.getReference(), documentSnapshot);
+          }
+
+          @Override
+          public void onError(Throwable throwable) {
+            futureList.setException(throwable);
+          }
+
+          @Override
+          public void onCompleted() {
+            List<DocumentSnapshot> documentSnapshotsList = new ArrayList<>();
+            for (DocumentReference documentReference : documentReferences) {
+              documentSnapshotsList.add(documentSnapshotMap.get(documentReference));
+            }
+            futureList.set(documentSnapshotsList);
+          }
+        });
     return futureList;
   }
 
diff --git a/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/it/ITSystemTest.java b/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/it/ITSystemTest.java
index de19f5492da7..eb9e56888efa 100644
--- a/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/it/ITSystemTest.java
+++ b/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/it/ITSystemTest.java
@@ -22,6 +22,7 @@
 import static java.util.Arrays.asList;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
@@ -29,6 +30,8 @@
 
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
+import com.google.api.core.SettableApiFuture;
+import com.google.api.gax.rpc.ApiStreamObserver;
 import com.google.cloud.Timestamp;
 import com.google.cloud.firestore.CollectionReference;
 import com.google.cloud.firestore.DocumentChange;
@@ -1327,4 +1330,53 @@ private static final class ListenerEvent {
       this.error = error;
     }
   }
+
+  @Test
+  public void getAllWithObserver() throws Exception {
+    DocumentReference ref1 = randomColl.document("doc1");
+    ref1.set(ALL_SUPPORTED_TYPES_MAP).get();
+
+    DocumentReference ref2 = randomColl.document("doc2");
+    ref2.set(ALL_SUPPORTED_TYPES_MAP).get();
+
+    DocumentReference ref3 = randomColl.document("doc3");
+
+    final List<DocumentSnapshot> documentSnapshots =
+        Collections.synchronizedList(new ArrayList<DocumentSnapshot>());
+    final DocumentReference[] documentReferences = {ref1, ref2, ref3};
+    final SettableApiFuture<Void> future = SettableApiFuture.create();
+    firestore.getAll(
+        documentReferences,
+        FieldMask.of("foo"),
+        new ApiStreamObserver<DocumentSnapshot>() {
+
+          @Override
+          public void onNext(DocumentSnapshot documentSnapshot) {
+            documentSnapshots.add(documentSnapshot);
+          }
+
+          @Override
+          public void onError(Throwable throwable) {
+            future.setException(throwable);
+          }
+
+          @Override
+          public void onCompleted() {
+            future.set(null);
+          }
+        });
+
+    future.get();
+
+    assertEquals(
+        ALL_SUPPORTED_TYPES_OBJECT, documentSnapshots.get(0).toObject(AllSupportedTypes.class));
+    assertEquals(
+        ALL_SUPPORTED_TYPES_OBJECT, documentSnapshots.get(1).toObject(AllSupportedTypes.class));
+    assertNotEquals(
+        ALL_SUPPORTED_TYPES_OBJECT, documentSnapshots.get(2).toObject(AllSupportedTypes.class));
+    assertEquals(ref1.getId(), documentSnapshots.get(0).getId());
+    assertEquals(ref2.getId(), documentSnapshots.get(1).getId());
+    assertEquals(ref3.getId(), documentSnapshots.get(2).getId());
+    assertEquals(3, documentSnapshots.size());
+  }
 }