diff --git a/pkg/provider/handlers/delete.go b/pkg/provider/handlers/delete.go
index b7cc740..34a94eb 100644
--- a/pkg/provider/handlers/delete.go
+++ b/pkg/provider/handlers/delete.go
@@ -42,6 +42,18 @@ func MakeDeleteHandler(client *containerd.Client, cni gocni.CNI) func(w http.Res
 
 		lookupNamespace := getRequestNamespace(readNamespaceFromQuery(r))
 
+		// Check if namespace exists, and it has the openfaas label
+		nsValid, err := validateNamespace(client, lookupNamespace)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if !nsValid {
+			http.Error(w, "namespace not valid", http.StatusBadRequest)
+			return
+		}
+
 		name := req.FunctionName
 
 		function, err := GetFunction(client, name, lookupNamespace)
diff --git a/pkg/provider/handlers/deploy.go b/pkg/provider/handlers/deploy.go
index b4919e7..3dbe63f 100644
--- a/pkg/provider/handlers/deploy.go
+++ b/pkg/provider/handlers/deploy.go
@@ -52,10 +52,25 @@ func MakeDeployHandler(client *containerd.Client, cni gocni.CNI, secretMountPath
 		}
 
 		namespace := getRequestNamespace(req.Namespace)
+
+		// Check if namespace exists, and it has the openfaas label
+		nsValid, err := validateNamespace(client, namespace)
+
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if !nsValid {
+			http.Error(w, "namespace not valid", http.StatusBadRequest)
+			return
+		}
+
 		namespaceSecretMountPath := getNamespaceSecretMountPath(secretMountPath, namespace)
 		err = validateSecrets(namespaceSecretMountPath, req.Secrets)
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
 		}
 
 		name := req.Service
diff --git a/pkg/provider/handlers/functions.go b/pkg/provider/handlers/functions.go
index 24ee9a6..aa08f76 100644
--- a/pkg/provider/handlers/functions.go
+++ b/pkg/provider/handlers/functions.go
@@ -2,6 +2,7 @@ package handlers
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"strings"
@@ -32,6 +33,17 @@ type Function struct {
 
 // ListFunctions returns a map of all functions with running tasks on namespace
 func ListFunctions(client *containerd.Client, namespace string) (map[string]*Function, error) {
+
+	// Check if namespace exists, and it has the openfaas label
+	nsValid, err := validateNamespace(client, namespace)
+	if err != nil {
+		return nil, err
+	}
+
+	if !nsValid {
+		return nil, errors.New("namespace not valid")
+	}
+
 	ctx := namespaces.WithNamespace(context.Background(), namespace)
 	functions := make(map[string]*Function)
 
diff --git a/pkg/provider/handlers/read.go b/pkg/provider/handlers/read.go
index 9707266..e2adc00 100644
--- a/pkg/provider/handlers/read.go
+++ b/pkg/provider/handlers/read.go
@@ -14,6 +14,17 @@ func MakeReadHandler(client *containerd.Client) func(w http.ResponseWriter, r *h
 	return func(w http.ResponseWriter, r *http.Request) {
 
 		lookupNamespace := getRequestNamespace(readNamespaceFromQuery(r))
+		// Check if namespace exists, and it has the openfaas label
+		nsValid, err := validateNamespace(client, lookupNamespace)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if !nsValid {
+			http.Error(w, "namespace not valid", http.StatusBadRequest)
+			return
+		}
 
 		res := []types.FunctionStatus{}
 		fns, err := ListFunctions(client, lookupNamespace)
diff --git a/pkg/provider/handlers/replicas.go b/pkg/provider/handlers/replicas.go
index 0c7d143..9e35839 100644
--- a/pkg/provider/handlers/replicas.go
+++ b/pkg/provider/handlers/replicas.go
@@ -16,6 +16,18 @@ func MakeReplicaReaderHandler(client *containerd.Client) func(w http.ResponseWri
 		functionName := vars["name"]
 		lookupNamespace := getRequestNamespace(readNamespaceFromQuery(r))
 
+		// Check if namespace exists, and it has the openfaas label
+		nsValid, err := validateNamespace(client, lookupNamespace)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if !nsValid {
+			http.Error(w, "namespace not valid", http.StatusBadRequest)
+			return
+		}
+
 		if f, err := GetFunction(client, functionName, lookupNamespace); err == nil {
 			found := types.FunctionStatus{
 				Name:              functionName,
diff --git a/pkg/provider/handlers/scale.go b/pkg/provider/handlers/scale.go
index e7dfa6a..c230876 100644
--- a/pkg/provider/handlers/scale.go
+++ b/pkg/provider/handlers/scale.go
@@ -41,6 +41,18 @@ func MakeReplicaUpdateHandler(client *containerd.Client, cni gocni.CNI) func(w h
 
 		namespace := getRequestNamespace(readNamespaceFromQuery(r))
 
+		// Check if namespace exists, and it has the openfaas label
+		nsValid, err := validateNamespace(client, namespace)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if !nsValid {
+			http.Error(w, "namespace not valid", http.StatusBadRequest)
+			return
+		}
+
 		name := req.ServiceName
 
 		if _, err := GetFunction(client, name, namespace); err != nil {
diff --git a/pkg/provider/handlers/secret.go b/pkg/provider/handlers/secret.go
index 3fc2f30..b52625c 100644
--- a/pkg/provider/handlers/secret.go
+++ b/pkg/provider/handlers/secret.go
@@ -49,6 +49,18 @@ func MakeSecretHandler(c *containerd.Client, mountPath string) func(w http.Respo
 func listSecrets(c *containerd.Client, w http.ResponseWriter, r *http.Request, mountPath string) {
 
 	lookupNamespace := getRequestNamespace(readNamespaceFromQuery(r))
+	// Check if namespace exists, and it has the openfaas label
+	nsValid, err := validateNamespace(c, lookupNamespace)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	if !nsValid {
+		http.Error(w, "namespace not valid", http.StatusBadRequest)
+		return
+	}
+
 	mountPath = getNamespaceSecretMountPath(mountPath, lookupNamespace)
 
 	files, err := ioutil.ReadDir(mountPath)
diff --git a/pkg/provider/handlers/update.go b/pkg/provider/handlers/update.go
index 812be77..6f35f4e 100644
--- a/pkg/provider/handlers/update.go
+++ b/pkg/provider/handlers/update.go
@@ -41,6 +41,19 @@ func MakeUpdateHandler(client *containerd.Client, cni gocni.CNI, secretMountPath
 		}
 		name := req.Service
 		namespace := getRequestNamespace(req.Namespace)
+
+		// Check if namespace exists, and it has the openfaas label
+		nsValid, err := validateNamespace(client, namespace)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if !nsValid {
+			http.Error(w, "namespace not valid", http.StatusBadRequest)
+			return
+		}
+
 		namespaceSecretMountPath := getNamespaceSecretMountPath(secretMountPath, namespace)
 
 		function, err := GetFunction(client, name, namespace)
diff --git a/pkg/provider/handlers/utils.go b/pkg/provider/handlers/utils.go
index 7f8938a..d2d71a9 100644
--- a/pkg/provider/handlers/utils.go
+++ b/pkg/provider/handlers/utils.go
@@ -1,6 +1,8 @@
 package handlers
 
 import (
+	"context"
+	"github.com/containerd/containerd"
 	"net/http"
 	"path"
 
@@ -23,3 +25,25 @@ func readNamespaceFromQuery(r *http.Request) string {
 func getNamespaceSecretMountPath(userSecretPath string, namespace string) string {
 	return path.Join(userSecretPath, namespace)
 }
+
+func validateNamespace(client *containerd.Client, namespace string) (bool, error) {
+	if namespace == faasd.FunctionNamespace {
+		return true, nil
+	}
+
+	store := client.NamespaceService()
+	labels, err := store.Labels(context.Background(), namespace)
+	if err != nil {
+		return false, err
+	}
+
+	value, found := labels["openfaas"]
+
+	if found {
+		if value == "true" {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}