diff --git a/cmd/juju/application/bundle.go b/cmd/juju/application/bundle.go
index 343f0a5..b4f2328 100644
--- a/cmd/juju/application/bundle.go
+++ b/cmd/juju/application/bundle.go
@@ -453,6 +453,20 @@
 		h.log.Infof("avoid creating other machines to host %s units", msg)
 		return nil
 	}
+	// Check if machine mapping was provided for services
+	for _, application := range services {
+		for _, toMach := range h.data.Applications[application].To {
+			if targetMach, ok := machinesMap[toMach]; ok {
+				if ! machinesProvided[targetMach] {
+					h.results[id] = targetMach
+					machinesProvided[targetMach] = true
+					msg = application
+					h.log.Infof("Assigned existing (pre-created) machine: %s to host: %s units", targetMach, msg)
+					return nil
+				}
+			}
+		}
+	}
 	cons, err := constraints.Parse(p.Constraints)
 	if err != nil {
 		// This should never happen, as the bundle is already verified.
diff --git a/cmd/juju/application/deploy.go b/cmd/juju/application/deploy.go
index 5c4889b..7ef423b 100644
--- a/cmd/juju/application/deploy.go
+++ b/cmd/juju/application/deploy.go
@@ -39,6 +39,10 @@
 
 var planURL = "https://api.jujucharms.com/omnibus/v2"
 
+// machinesMap stores map from logical machines to existing machines
+var machinesMap map[string]string
+var machinesProvided map[string]bool
+
 type CharmAdder interface {
 	AddLocalCharm(*charm.URL, charm.Charm) (*charm.URL, error)
 	AddCharm(*charm.URL, params.Channel) error
@@ -255,6 +259,7 @@
 	ConstraintsStr  string
 	Constraints     constraints.Value
 	BindToSpaces    string
+	MachinesMapStr  string
 
 	// TODO(axw) move this to UnitCommandBase once we support --storage
 	// on add-unit too.
@@ -417,7 +422,7 @@
 	// charmOnlyFlags and bundleOnlyFlags are used to validate flags based on
 	// whether we are deploying a charm or a bundle.
 	charmOnlyFlags        = []string{"bind", "config", "constraints", "force", "n", "num-units", "series", "to", "resource"}
-	bundleOnlyFlags       = []string{}
+	bundleOnlyFlags       = []string{"machines"}
 	modelCommandBaseFlags = []string{"B", "no-browser-login"}
 )
 
@@ -435,6 +440,7 @@
 	f.Var(storageFlag{&c.Storage, &c.BundleStorage}, "storage", "Charm storage constraints")
 	f.Var(stringMap{&c.Resources}, "resource", "Resource to be uploaded to the controller")
 	f.StringVar(&c.BindToSpaces, "bind", "", "Configure application endpoint bindings to spaces")
+	f.StringVar(&c.MachinesMapStr, "machines", "", "Map logical machines to existing machines (pre-created)")
 
 	for _, step := range c.Steps {
 		step.SetFlags(f)
@@ -462,6 +468,9 @@
 	}
 
 	if err := c.parseBind(); err != nil {
+		return err
+	}
+	if err := c.parseMachines(); err != nil {
 		return err
 	}
 	return c.UnitCommandBase.Init(args)
@@ -649,6 +658,48 @@
 	return nil
 }
 
+const parseMachinesErrorPrefix = "--machines must be in the form '<logical-name>=<target-name> ...'. "
+
+// parseMachines parses the --machines option. Valid forms are:
+//   e.g. "dbserver=0 webserver=1"
+func (c *DeployCommand) parseMachines() error {
+	mapping := make(map[string]string)
+	if c.MachinesMapStr == "" {
+		return nil
+	}
+
+	for _, s := range strings.Split(c.MachinesMapStr, " ") {
+		s = strings.TrimSpace(s)
+		if s == "" {
+			continue
+		}
+
+		v := strings.Split(s, "=")
+		var lmachine, tmachine string
+		switch len(v) {
+		case 1:
+			return errors.New(parseMachinesErrorPrefix)
+		case 2:
+			if v[0] == "" {
+				return errors.New(parseMachinesErrorPrefix + "Found = without target machine name.")
+			}
+			lmachine = v[0]
+			tmachine = v[1]
+		default:
+			return errors.New(parseMachinesErrorPrefix + "Found multiple = in binding. Did you forget to space-separate the binding list?")
+		}
+
+		//TODO: add checking if target machine exists - perhaps isValidMachine
+		//if !isValidMachine(machine) {
+		//	return errors.New(parseMachinesErrorPrefix + "Target machine name invalid.")
+		//}
+		mapping[lmachine] = tmachine
+	}
+	machinesMap = mapping
+	machinesProvided = make(map[string]bool)
+	return nil
+}
+
 func (c *DeployCommand) Run(ctx *cmd.Context) error {
 	var err error
 	c.Constraints, err = common.ParseConstraints(ctx, c.ConstraintsStr)