diff --git a/provisioner/shell/provisioner.go b/provisioner/shell/provisioner.go
index f66128bf8..cd447f1d8 100644
--- a/provisioner/shell/provisioner.go
+++ b/provisioner/shell/provisioner.go
@@ -5,6 +5,7 @@ package shell
 import (
 	"bytes"
 	"fmt"
+	"errors"
 	"github.com/mitchellh/iochan"
 	"github.com/mitchellh/mapstructure"
 	"github.com/mitchellh/packer/packer"
@@ -18,6 +19,10 @@ import (
 const DefaultRemotePath = "/tmp/script.sh"
 
 type config struct {
+	// An inline script to execute. Multiple strings are all executed
+	// in the context of a single shell.
+	Inline []string
+
 	// The local path of the shell script to upload and execute.
 	Path string
 
@@ -49,10 +54,32 @@ func (p *Provisioner) Prepare(raws ...interface{}) error {
 		p.config.ExecuteCommand = "chmod +x {{.Path}} && {{.Path}}"
 	}
 
+	if p.config.Inline != nil && len(p.config.Inline) == 0 {
+		p.config.Inline = nil
+	}
+
 	if p.config.RemotePath == "" {
 		p.config.RemotePath = DefaultRemotePath
 	}
 
+	errs := make([]error, 0)
+
+	if p.config.Path == "" && p.config.Inline == nil {
+		errs = append(errs, errors.New("Either a path or inline script must be specified."))
+	} else if p.config.Path != "" && p.config.Inline != nil {
+		errs = append(errs, errors.New("Only a path or an inline script can be specified, not both."))
+	}
+
+	if p.config.Path != "" {
+		if _, err := os.Stat(p.config.Path); err != nil {
+			errs = append(errs, fmt.Errorf("Bad script path: %s", err))
+		}
+	}
+
+	if len(errs) > 0 {
+		return &packer.MultiError{errs}
+	}
+
 	return nil
 }
 
diff --git a/provisioner/shell/provisioner_test.go b/provisioner/shell/provisioner_test.go
index 5da089187..a7ade6d5a 100644
--- a/provisioner/shell/provisioner_test.go
+++ b/provisioner/shell/provisioner_test.go
@@ -2,9 +2,17 @@ package shell
 
 import (
 	"github.com/mitchellh/packer/packer"
+	"io/ioutil"
+	"os"
 	"testing"
 )
 
+func testConfig() map[string]interface{} {
+	return map[string]interface{}{
+		"inline": []interface{}{"foo", "bar"},
+	}
+}
+
 func TestProvisioner_Impl(t *testing.T) {
 	var raw interface{}
 	raw = &Provisioner{}
@@ -14,10 +22,10 @@ func TestProvisioner_Impl(t *testing.T) {
 }
 
 func TestProvisionerPrepare_Defaults(t *testing.T) {
-	raw := map[string]interface{}{}
+	var p Provisioner
+	config := testConfig()
 
-	p := &Provisioner{}
-	err := p.Prepare(raw)
+	err := p.Prepare(config)
 	if err != nil {
 		t.Fatalf("err: %s", err)
 	}
@@ -26,3 +34,54 @@ func TestProvisionerPrepare_Defaults(t *testing.T) {
 		t.Errorf("unexpected remote path: %s", p.config.RemotePath)
 	}
 }
+
+func TestProvisionerPrepare_Path(t *testing.T) {
+	var p Provisioner
+	config := testConfig()
+	delete(config, "inline")
+
+	config["path"] = "/this/should/not/exist"
+	err := p.Prepare(config)
+	if err == nil {
+		t.Fatal("should have error")
+	}
+
+	// Test with a good one
+	tf, err := ioutil.TempFile("", "packer")
+	if err != nil {
+		t.Fatalf("error tempfile: %s", err)
+	}
+	defer os.Remove(tf.Name())
+
+	config["path"] = tf.Name()
+	err = p.Prepare(config)
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+}
+
+func TestProvisionerPrepare_PathAndInline(t *testing.T) {
+	var p Provisioner
+	config := testConfig()
+
+	delete(config, "inline")
+	delete(config, "path")
+	err := p.Prepare(config)
+	if err == nil {
+		t.Fatal("should have error")
+	}
+
+	// Test with both
+	tf, err := ioutil.TempFile("", "packer")
+	if err != nil {
+		t.Fatalf("error tempfile: %s", err)
+	}
+	defer os.Remove(tf.Name())
+
+	config["inline"] = []interface{}{"foo"}
+	config["path"] = tf.Name()
+	err = p.Prepare(config)
+	if err == nil {
+		t.Fatal("should have error")
+	}
+}