diff --git a/bulk_indexer.go b/bulk_indexer.go
index cf1e34d..f75973d 100644
--- a/bulk_indexer.go
+++ b/bulk_indexer.go
@@ -49,6 +49,15 @@ import (
 // of concurrent bulk requests. This way we can ensure bulk requests have the
 // maximum possible size, based on configuration and throughput.
 
+const (
+	// Actions are all the actions that can be used when indexing data.
+	// `create` will be used by default.
+	ActionCreate = "create"
+	ActionDelete = "delete"
+	ActionIndex  = "index"
+	ActionUpdate = "update"
+)
+
 // BulkIndexerConfig holds configuration for BulkIndexer.
 type BulkIndexerConfig struct {
 	// Client holds the Elasticsearch client.
@@ -280,13 +289,25 @@ type BulkIndexerItem struct {
 	Index            string
 	DocumentID       string
 	Pipeline         string
+	Action           string
 	Body             io.WriterTo
 	DynamicTemplates map[string]string
 }
 
 // Add encodes an item in the buffer.
 func (b *BulkIndexer) Add(item BulkIndexerItem) error {
-	b.writeMeta(item.Index, item.DocumentID, item.Pipeline, item.DynamicTemplates)
+	action := item.Action
+	if action == "" {
+		action = ActionCreate
+	}
+
+	switch action {
+	case ActionCreate, ActionDelete, ActionIndex, ActionUpdate:
+	default:
+		return fmt.Errorf("%s is not a valid action", action)
+	}
+
+	b.writeMeta(item.Index, item.DocumentID, item.Pipeline, action, item.DynamicTemplates)
 	if _, err := item.Body.WriteTo(b.writer); err != nil {
 		return fmt.Errorf("failed to write bulk indexer item: %w", err)
 	}
@@ -297,8 +318,11 @@ func (b *BulkIndexer) Add(item BulkIndexerItem) error {
 	return nil
 }
 
-func (b *BulkIndexer) writeMeta(index, documentID, pipeline string, dynamicTemplates map[string]string) {
-	b.jsonw.RawString(`{"create":{`)
+func (b *BulkIndexer) writeMeta(index, documentID, pipeline, action string, dynamicTemplates map[string]string) {
+	b.jsonw.RawString(`{"`)
+	b.jsonw.RawString(action)
+	b.jsonw.RawString(`":{`)
+
 	first := true
 	if documentID != "" {
 		b.jsonw.RawString(`"_id":`)
diff --git a/bulk_indexer_test.go b/bulk_indexer_test.go
index 7c52483..34dfccd 100644
--- a/bulk_indexer_test.go
+++ b/bulk_indexer_test.go
@@ -29,6 +29,7 @@ import (
 
 	"github.com/elastic/go-docappender/v2"
 	"github.com/elastic/go-docappender/v2/docappendertest"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
@@ -203,3 +204,65 @@ func TestPipeline(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, int64(2), stat.Indexed)
 }
+
+func TestAction(t *testing.T) {
+	client := docappendertest.NewMockElasticsearchClient(t, func(w http.ResponseWriter, r *http.Request) {
+		_, result := docappendertest.DecodeBulkRequest(r)
+		err := json.NewEncoder(w).Encode(result)
+		require.NoError(t, err)
+
+		actions := []string{}
+		for _, itemsMap := range result.Items {
+			for a := range itemsMap {
+				actions = append(actions, a)
+			}
+		}
+
+		require.Equal(t, []string{"create", "update", "delete"}, actions)
+	})
+	indexer, err := docappender.NewBulkIndexer(docappender.BulkIndexerConfig{
+		Client: client,
+	})
+	require.NoError(t, err)
+
+	err = indexer.Add(docappender.BulkIndexerItem{
+		Index: "testidx",
+		Body: newJSONReader(map[string]any{
+			"@timestamp": time.Now().Format(docappendertest.TimestampFormat),
+		}),
+	})
+	require.NoError(t, err)
+
+	err = indexer.Add(docappender.BulkIndexerItem{
+		Index:  "testidx",
+		Action: "update",
+		Body: newJSONReader(map[string]any{
+			"@timestamp": time.Now().Format(docappendertest.TimestampFormat),
+		}),
+	})
+	require.NoError(t, err)
+
+	err = indexer.Add(docappender.BulkIndexerItem{
+		Index:    "testidx",
+		Action:   "delete",
+		Pipeline: "test-pipeline2",
+		Body: newJSONReader(map[string]any{
+			"@timestamp": time.Now().Format(docappendertest.TimestampFormat),
+		}),
+	})
+	require.NoError(t, err)
+
+	err = indexer.Add(docappender.BulkIndexerItem{
+		Index:    "testidx",
+		Action:   "foobar",
+		Pipeline: "test-pipeline2",
+		Body: newJSONReader(map[string]any{
+			"@timestamp": time.Now().Format(docappendertest.TimestampFormat),
+		}),
+	})
+	assert.Error(t, err)
+
+	stat, err := indexer.Flush(context.Background())
+	require.NoError(t, err)
+	require.Equal(t, int64(3), stat.Indexed)
+}