diff --git a/cmd/run/main.go b/cmd/run/main.go
index 5163223..87de0fe 100644
--- a/cmd/run/main.go
+++ b/cmd/run/main.go
@@ -62,6 +62,6 @@ var Cmd = &cobra.Command{
 func init() {
 	flags := Cmd.Flags()
 	flags.BoolVarP(&verbose, "verbose", "v", verbose, "Verbose logging")
-	flags.StringToStringVarP(&cmdInputs, "inputs", "i", cmdInputs, "Input variables")
-	flags.StringVarP(&inputFile, "inputfile", "f", inputFile, "Input variables file")
+	flags.StringToStringVarP(&cmdInputs, "config", "c", cmdInputs, "Config variable")
+	flags.StringVarP(&inputFile, "configFile", "f", inputFile, "Config file")
 }
diff --git a/config/config.go b/config/config.go
index 7f69877..f1b3ac2 100644
--- a/config/config.go
+++ b/config/config.go
@@ -2,7 +2,7 @@ package config
 
 import "strings"
 
-type Config map[string]string
+type Config map[string]*string
 
 type Type string
 
diff --git a/playbook/execute.go b/playbook/execute.go
index 2706566..0072dad 100644
--- a/playbook/execute.go
+++ b/playbook/execute.go
@@ -3,6 +3,7 @@ package playbook
 import (
 	"fmt"
 	"path/filepath"
+	"strings"
 
 	"github.com/bmeg/flame"
 	"github.com/bmeg/sifter/logger"
@@ -22,6 +23,7 @@ func fileExists(filename string) bool {
 
 func (pb *Playbook) PrepConfig(inputs map[string]string, workdir string) (map[string]string, error) {
 	workdir, _ = filepath.Abs(workdir)
+	missing := map[string]bool{}
 	out := map[string]string{}
 	for _, v := range pb.GetConfigFields() {
 		if val, ok := inputs[v.Name]; ok {
@@ -32,16 +34,27 @@ func (pb *Playbook) PrepConfig(inputs map[string]string, workdir string) (map[st
 				out[v.Name] = val
 			}
 		} else if val, ok := pb.Config[v.Name]; ok {
-			if v.IsFile() || v.IsDir() {
-				defaultPath := filepath.Join(filepath.Dir(pb.path), val)
-				out[v.Name], _ = filepath.Abs(defaultPath)
+			if val != nil {
+				if v.IsFile() || v.IsDir() {
+					defaultPath := filepath.Join(filepath.Dir(pb.path), *val)
+					out[v.Name], _ = filepath.Abs(defaultPath)
+				} else {
+					out[v.Name] = *val
+				}
 			} else {
-				out[v.Name] = val
+				missing[v.Name] = true
 			}
 		} else {
 			return nil, fmt.Errorf("config %s not defined", v.Name)
 		}
 	}
+	if len(missing) > 0 {
+		o := []string{}
+		for k := range missing {
+			o = append(o, k)
+		}
+		return nil, fmt.Errorf("missing inputs: %s", strings.Join(o, ","))
+	}
 	return out, nil
 }