diff --git a/README.md b/README.md
index 1a674de..6cd7fd8 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,8 @@ if err != nil {
 stackAuth := management.StackAuth{
     ApiKey:          "foobar", // Required
     ManagementToken: "secret", // Optional
-})
+    Branch:          "development", // Optional
+}
 
 instance, err := client.Stack(stackAuth)
 if err != nil {
diff --git a/management/stack_instance.go b/management/stack_instance.go
index fb93fb2..d40c7a7 100644
--- a/management/stack_instance.go
+++ b/management/stack_instance.go
@@ -13,6 +13,7 @@ type StackInstance struct {
 type StackAuth struct {
 	ApiKey          string
 	ManagementToken string
+	Branch          string
 }
 
 // Stack creates a new StackInstance which can be used for actions on the
@@ -39,5 +40,8 @@ func (si *StackInstance) headers() http.Header {
 	} else {
 		header.Add("authtoken", si.client.authToken)
 	}
+	if si.auth.Branch != "" {
+		header.Add("branch", si.auth.Branch)
+	}
 	return header
 }