diff --git a/test/extended/machines/scale.go b/test/extended/machines/scale.go
new file mode 100644
index 000000000000..ab25fef63df3
--- /dev/null
+++ b/test/extended/machines/scale.go
@@ -0,0 +1,215 @@
+package operators
+
+import (
+	"fmt"
+	"strconv"
+	"time"
+
+	"k8s.io/client-go/kubernetes"
+
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/client-go/discovery"
+	"k8s.io/client-go/restmapper"
+	"k8s.io/client-go/scale"
+
+	g "github.com/onsi/ginkgo"
+	o "github.com/onsi/gomega"
+	"github.com/stretchr/objx"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/dynamic"
+	e2e "k8s.io/kubernetes/test/e2e/framework"
+)
+
+const (
+	machineAPIGroup       = "machine.openshift.io"
+	machineSetOwningLabel = "machine.openshift.io/cluster-api-machineset"
+	scalingTime           = 7 * time.Minute
+)
+
+// machineSetClient returns a client for machines scoped to the proper namespace
+func machineSetClient(dc dynamic.Interface) dynamic.ResourceInterface {
+	machineSetClient := dc.Resource(schema.GroupVersionResource{Group: machineAPIGroup, Resource: "machinesets", Version: "v1beta1"})
+	return machineSetClient.Namespace(machineAPINamespace)
+}
+
+// listWorkerMachineSets list all worker machineSets
+func listWorkerMachineSets(dc dynamic.Interface) ([]objx.Map, error) {
+	mc := machineSetClient(dc)
+	obj, err := mc.List(metav1.ListOptions{})
+	if err != nil {
+		return nil, err
+	}
+	machineSets := []objx.Map{}
+	for _, ms := range objects(objx.Map(obj.UnstructuredContent()).Get("items")) {
+		e2e.Logf("Labels %v", ms.Get("spec.selector.matchLabels"))
+		labels := (*ms.Get("spec.selector.matchLabels")).Data().(map[string]interface{})
+		if val, ok := labels[machineLabelRole]; ok {
+			if val == "worker" {
+				machineSets = append(machineSets, ms)
+				continue
+			}
+		}
+	}
+	return machineSets, nil
+}
+
+func getMachineSetReplicaNumber(item objx.Map) int {
+	replicas, _ := strconv.Atoi(item.Get("spec.replicas").String())
+	return replicas
+}
+
+// getNodesFromMachineSet returns an array of nodes backed by machines owned by a given machineSet
+func getNodesFromMachineSet(c *kubernetes.Clientset, dc dynamic.Interface, machineSetName string) ([]*corev1.Node, error) {
+	machines, err := listMachines(dc, fmt.Sprintf("%s=%s", machineSetOwningLabel, machineSetName))
+	if err != nil {
+		return nil, fmt.Errorf("failed to list machines: %v", err)
+	}
+
+	// fetch nodes
+	allWorkerNodes, err := c.CoreV1().Nodes().List(metav1.ListOptions{
+		LabelSelector: nodeLabelSelectorWorker,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to list worker nodes: %v", err)
+	}
+
+	machineToNodes, match := mapMachineNameToNodeName(machines, allWorkerNodes.Items)
+	if !match {
+		return nil, fmt.Errorf("not all machines have a node reference: %v", machineToNodes)
+	}
+	var nodes []*corev1.Node
+	for machineName := range machineToNodes {
+		node, err := c.CoreV1().Nodes().Get(machineToNodes[machineName], metav1.GetOptions{})
+		if err != nil {
+			return nil, fmt.Errorf("failed to get worker nodes %q: %v", machineToNodes[machineName], err)
+		}
+		nodes = append(nodes, node)
+	}
+
+	return nodes, nil
+}
+
+func getScaleClient() (scale.ScalesGetter, error) {
+	cfg, err := e2e.LoadConfig()
+	if err != nil {
+		return nil, fmt.Errorf("error getting config: %v", err)
+	}
+
+	discoveryClient, err := discovery.NewDiscoveryClientForConfig(cfg)
+	if err != nil {
+		return nil, fmt.Errorf("error discovering client: %v", err)
+	}
+
+	groupResources, err := restmapper.GetAPIGroupResources(discoveryClient)
+	if err != nil {
+		return nil, fmt.Errorf("error getting API resources: %v", err)
+	}
+	restMapper := restmapper.NewDiscoveryRESTMapper(groupResources)
+	scaleKindResolver := scale.NewDiscoveryScaleKindResolver(discoveryClient)
+
+	scaleClient, err := scale.NewForConfig(cfg, restMapper, dynamic.LegacyAPIPathResolverFunc, scaleKindResolver)
+	if err != nil {
+		return nil, fmt.Errorf("error creating scale client: %v", err)
+	}
+	return scaleClient, nil
+}
+
+// scaleMachineSet scales a machineSet with a given name to the given number of replicas
+func scaleMachineSet(name string, replicas int) error {
+	scaleClient, err := getScaleClient()
+	if err != nil {
+		return fmt.Errorf("error calling getScaleClient: %v", err)
+	}
+
+	scale, err := scaleClient.Scales(machineAPINamespace).Get(schema.GroupResource{Group: machineAPIGroup, Resource: "MachineSet"}, name)
+	if err != nil {
+		return fmt.Errorf("error calling scaleClient.Scales get: %v", err)
+	}
+
+	scaleUpdate := scale.DeepCopy()
+	scaleUpdate.Spec.Replicas = int32(replicas)
+	_, err = scaleClient.Scales(machineAPINamespace).Update(schema.GroupResource{Group: machineAPIGroup, Resource: "MachineSet"}, scaleUpdate)
+	if err != nil {
+		return fmt.Errorf("error calling scaleClient.Scales update while setting replicas to %d: %v", err, replicas)
+	}
+	return nil
+}
+
+var _ = g.Describe("[Feature:Machines][Serial] Managed cluster should", func() {
+	g.It("grow and decrease when scaling different machineSets simultaneously", func() {
+		// expect new nodes to come up for machineSet
+		verifyNodeScalingFunc := func(c *kubernetes.Clientset, dc dynamic.Interface, expectedScaleOut int, machineSet objx.Map) bool {
+			nodes, err := getNodesFromMachineSet(c, dc, machineName(machineSet))
+			if err != nil {
+				e2e.Logf("Error getting nodes from machineSet: %v", err)
+				return false
+			}
+			e2e.Logf("node count : %v, expectedCount %v", len(nodes), expectedScaleOut)
+			for i := range nodes {
+				e2e.Logf("node: %v", nodes[i].Name)
+				if !isNodeReady(*nodes[i]) {
+					e2e.Logf("Node %q is not ready", nodes[i].Name)
+					return false
+				}
+			}
+			return len(nodes) == expectedScaleOut
+		}
+
+		cfg, err := e2e.LoadConfig()
+		o.Expect(err).NotTo(o.HaveOccurred())
+		c, err := e2e.LoadClientset()
+		o.Expect(err).NotTo(o.HaveOccurred())
+		dc, err := dynamic.NewForConfig(cfg)
+		o.Expect(err).NotTo(o.HaveOccurred())
+
+		g.By("fetching worker machineSets")
+		machineSets, err := listWorkerMachineSets(dc)
+		o.Expect(err).NotTo(o.HaveOccurred())
+		if len(machineSets) == 0 {
+			e2e.Skipf("Expects at least one worker machineset. Found none!!!")
+		}
+
+		g.By("checking initial cluster workers size")
+		nodeList, err := c.CoreV1().Nodes().List(metav1.ListOptions{
+			LabelSelector: nodeLabelSelectorWorker,
+		})
+		o.Expect(err).NotTo(o.HaveOccurred())
+
+		initialNumberOfWorkers := len(nodeList.Items)
+
+		initialReplicasMachineSets := map[string]int{}
+
+		for _, machineSet := range machineSets {
+			initialReplicasMachineSet := getMachineSetReplicaNumber(machineSet)
+			expectedScaleOut := initialReplicasMachineSet + 1
+			initialReplicasMachineSets[machineName(machineSet)] = initialReplicasMachineSet
+			g.By(fmt.Sprintf("scaling %q from %d to %d replicas", machineName(machineSet), initialReplicasMachineSet, expectedScaleOut))
+			err = scaleMachineSet(machineName(machineSet), expectedScaleOut)
+			o.Expect(err).NotTo(o.HaveOccurred())
+		}
+		for _, machineSet := range machineSets {
+			expectedScaleOut := initialReplicasMachineSets[machineName(machineSet)] + 1
+			o.Eventually(func() bool {
+				return verifyNodeScalingFunc(c, dc, expectedScaleOut, machineSet)
+			}, scalingTime, 5*time.Second).Should(o.BeTrue())
+		}
+
+		for _, machineSet := range machineSets {
+			scaledReplicasMachineSet := initialReplicasMachineSets[machineName(machineSet)] + 1
+			g.By(fmt.Sprintf("scaling %q from %d to %d replicas", machineName(machineSet), scaledReplicasMachineSet, initialReplicasMachineSets[machineName(machineSet)]))
+			err = scaleMachineSet(machineName(machineSet), initialReplicasMachineSets[machineName(machineSet)])
+			o.Expect(err).NotTo(o.HaveOccurred())
+		}
+
+		g.By(fmt.Sprintf("waiting for cluster to get back to original size. Final size should be %d worker nodes", initialNumberOfWorkers))
+		o.Eventually(func() bool {
+			nodeList, err := c.CoreV1().Nodes().List(metav1.ListOptions{
+				LabelSelector: nodeLabelSelectorWorker,
+			})
+			o.Expect(err).NotTo(o.HaveOccurred())
+			return len(nodeList.Items) == initialNumberOfWorkers
+		}, 1*time.Minute, 5*time.Second).Should(o.BeTrue())
+	})
+})
diff --git a/test/extended/machines/workers.go b/test/extended/machines/workers.go
index 7afa4eb68fc7..a235434269f3 100644
--- a/test/extended/machines/workers.go
+++ b/test/extended/machines/workers.go
@@ -22,6 +22,7 @@ import (
 const (
 	machineAPINamespace     = "openshift-machine-api"
 	nodeLabelSelectorWorker = "node-role.kubernetes.io/worker"
+	machineLabelRole        = "machine.openshift.io/cluster-api-machine-role"
 
 	// time after purge of machine to wait for replacement and ready node
 	// TODO: tighten this further based on node lifecycle controller [appears to be ~5m30s]
@@ -91,6 +92,20 @@ func mapNodeNameToMachine(nodes []corev1.Node, machines []objx.Map) (map[string]
 	return result, len(nodes) == len(result)
 }
 
+// mapMachineNameToNodeName returns a tuple (map node to machine by name, true if a match is found for every node)
+func mapMachineNameToNodeName(machines []objx.Map, nodes []corev1.Node) (map[string]string, bool) {
+	result := map[string]string{}
+	for i := range machines {
+		for j := range nodes {
+			if nodes[j].Name == nodeNameFromNodeRef(machines[i]) {
+				result[machineName(machines[i])] = nodes[j].Name
+				break
+			}
+		}
+	}
+	return result, len(machines) == len(result)
+}
+
 func isNodeReady(node corev1.Node) bool {
 	for _, c := range node.Status.Conditions {
 		if c.Type == corev1.NodeReady {