diff --git a/fleetctl/destroy.go b/fleetctl/destroy.go
index d00778aa1..28154ac01 100644
--- a/fleetctl/destroy.go
+++ b/fleetctl/destroy.go
@@ -29,6 +29,10 @@ Destroyed units are impossible to start unless re-submitted.`,
 }
 
 func runDestroyUnits(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	for _, v := range args {
 		name := unitNameMangle(v)
 		err := cAPI.DestroyUnit(name)
diff --git a/fleetctl/load.go b/fleetctl/load.go
index 497f86058..1841973a6 100644
--- a/fleetctl/load.go
+++ b/fleetctl/load.go
@@ -46,6 +46,10 @@ func init() {
 }
 
 func runLoadUnits(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	if err := lazyCreateUnits(args); err != nil {
 		stderr("Error creating units: %v", err)
 		return 1
diff --git a/fleetctl/start.go b/fleetctl/start.go
index 77ea0d343..fe7ce27b1 100644
--- a/fleetctl/start.go
+++ b/fleetctl/start.go
@@ -54,6 +54,10 @@ func init() {
 }
 
 func runStartUnit(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	if err := lazyCreateUnits(args); err != nil {
 		stderr("Error creating units: %v", err)
 		return 1
diff --git a/fleetctl/status.go b/fleetctl/status.go
index c1b065f1b..0953a265c 100644
--- a/fleetctl/status.go
+++ b/fleetctl/status.go
@@ -44,6 +44,10 @@ func init() {
 }
 
 func runStatusUnits(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	units, err := cAPI.Units()
 	if err != nil {
 		stderr("Error retrieving unit: %v", err)
diff --git a/fleetctl/stop.go b/fleetctl/stop.go
index 262946bfb..107a167e3 100644
--- a/fleetctl/stop.go
+++ b/fleetctl/stop.go
@@ -52,6 +52,10 @@ func init() {
 }
 
 func runStopUnit(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	units, err := findUnits(args)
 	if err != nil {
 		stderr("%v", err)
diff --git a/fleetctl/submit.go b/fleetctl/submit.go
index cbfe03f93..7be065b13 100644
--- a/fleetctl/submit.go
+++ b/fleetctl/submit.go
@@ -36,6 +36,10 @@ func init() {
 }
 
 func runSubmitUnits(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	if err := lazyCreateUnits(args); err != nil {
 		stderr("Error creating units: %v", err)
 		exit = 1
diff --git a/fleetctl/unload.go b/fleetctl/unload.go
index 6758f2825..a95514bfb 100644
--- a/fleetctl/unload.go
+++ b/fleetctl/unload.go
@@ -36,6 +36,10 @@ func init() {
 }
 
 func runUnloadUnit(args []string) (exit int) {
+	if len(args) != 1 {
+		stderr("One unit file must be provided.")
+		return 1
+	}
 	units, err := findUnits(args)
 	if err != nil {
 		stderr("%v", err)