diff --git a/README.md b/README.md
index 0a9b69c6d..7e8af5757 100644
--- a/README.md
+++ b/README.md
@@ -76,7 +76,7 @@ Installing on Ubuntu 12.04 and 12.10
 
     ```bash
     cd docker-master
-    sudo ./docker run -a -i -t base /bin/bash
+    sudo ./docker run -i -t base /bin/bash
     ```
 
     Consider adding docker to your `PATH` for simplicity.
@@ -136,7 +136,7 @@ docker import base
 
 # Run an interactive shell in the base image,
 # allocate a tty, attach stdin and stdout
-docker run -a -i -t base /bin/bash
+docker run -i -t base /bin/bash
 ```
 
 
@@ -148,7 +148,7 @@ Starting a long-running worker process
 (docker -d || echo "Docker daemon already running") &
 
 # Start a very useful long-running process
-JOB=$(docker run base /bin/sh -c "while true; do echo Hello world; sleep 1; done")
+JOB=$(docker run -d base /bin/sh -c "while true; do echo Hello world; sleep 1; done")
 
 # Collect the output of the job so far
 docker logs $JOB
@@ -171,7 +171,7 @@ Expose a service on a TCP port
 
 ```bash
 # Expose port 4444 of this container, and tell netcat to listen on it
-JOB=$(docker run -p 4444 base /bin/nc -l -p 4444)
+JOB=$(docker run -d -p 4444 base /bin/nc -l -p 4444)
 
 # Which public port is NATed to my container?
 PORT=$(docker port $JOB 4444)
diff --git a/commands.go b/commands.go
index 443d192bd..9e2bdbc70 100644
--- a/commands.go
+++ b/commands.go
@@ -783,6 +783,18 @@ func (p *ports) Set(value string) error {
 	return nil
 }
 
+// ListOpts type
+type ListOpts []string
+
+func (opts *ListOpts) String() string {
+	return fmt.Sprint(*opts)
+}
+
+func (opts *ListOpts) Set(value string) error {
+	*opts = append(*opts, value)
+	return nil
+}
+
 func (srv *Server) CmdTag(stdin io.ReadCloser, stdout io.Writer, args ...string) error {
 	cmd := rcli.Subcmd(stdout, "tag", "[OPTIONS] IMAGE REPOSITORY [TAG]", "Tag an image into a repository")
 	force := cmd.Bool("f", false, "Force")
@@ -799,35 +811,24 @@ func (srv *Server) CmdTag(stdin io.ReadCloser, stdout io.Writer, args ...string)
 func (srv *Server) CmdRun(stdin io.ReadCloser, stdout io.Writer, args ...string) error {
 	cmd := rcli.Subcmd(stdout, "run", "[OPTIONS] IMAGE COMMAND [ARG...]", "Run a command in a new container")
 	fl_user := cmd.String("u", "", "Username or UID")
-	fl_attach := cmd.Bool("a", false, "Attach stdin and stdout")
+	fl_detach := cmd.Bool("d", false, "Detached mode: leave the container running in the background")
 	fl_stdin := cmd.Bool("i", false, "Keep stdin open even if not attached")
 	fl_tty := cmd.Bool("t", false, "Allocate a pseudo-tty")
 	fl_memory := cmd.Int64("m", 0, "Memory limit (in bytes)")
 	var fl_ports ports
 
 	cmd.Var(&fl_ports, "p", "Map a network port to the container")
+	var fl_env ListOpts
+	cmd.Var(&fl_env, "e", "Set environment variables")
 	if err := cmd.Parse(args); err != nil {
 		return nil
 	}
+	if cmd.NArg() < 2 {
+		cmd.Usage()
+		return nil
+	}
 	name := cmd.Arg(0)
-	var cmdline []string
-
-	if len(cmd.Args()) >= 2 {
-		cmdline = cmd.Args()[1:]
-	}
-	// Choose a default image if needed
-	if name == "" {
-		name = "base"
-	}
-
-	// Choose a default command if needed
-	if len(cmdline) == 0 {
-		*fl_stdin = true
-		*fl_tty = true
-		*fl_attach = true
-		cmdline = []string{"/bin/bash", "-i"}
-	}
-
+	cmdline := cmd.Args()[1:]
 	// Create new container
 	container, err := srv.runtime.Create(cmdline[0], cmdline[1:], name,
 		&Config{
@@ -836,6 +837,7 @@ func (srv *Server) CmdRun(stdin io.ReadCloser, stdout io.Writer, args ...string)
 			Tty:       *fl_tty,
 			OpenStdin: *fl_stdin,
 			Memory:    *fl_memory,
+			Env:       fl_env,
 		})
 	if err != nil {
 		return errors.New("Error creating container: " + err.Error())
@@ -845,7 +847,7 @@ func (srv *Server) CmdRun(stdin io.ReadCloser, stdout io.Writer, args ...string)
 		if err != nil {
 			return err
 		}
-		if *fl_attach {
+		if !*fl_detach {
 			Go(func() error {
 				_, err := io.Copy(cmd_stdin, stdin)
 				cmd_stdin.Close()
@@ -854,7 +856,7 @@ func (srv *Server) CmdRun(stdin io.ReadCloser, stdout io.Writer, args ...string)
 		}
 	}
 	// Run the container
-	if *fl_attach {
+	if !*fl_detach {
 		cmd_stderr, err := container.StderrPipe()
 		if err != nil {
 			return err
diff --git a/container.go b/container.go
index ea091b8fa..2b94fa7e0 100644
--- a/container.go
+++ b/container.go
@@ -53,6 +53,7 @@ type Config struct {
 	Ports      []int
 	Tty        bool // Attach standard streams to a tty, including stdin if it is not closed.
 	OpenStdin  bool // Open stdin
+	Env        []string
 }
 
 type NetworkSettings struct {
@@ -200,6 +201,15 @@ func (container *Container) Start() error {
 
 	container.cmd = exec.Command("/usr/bin/lxc-start", params...)
 
+	// Setup environment
+	container.cmd.Env = append(
+		[]string{
+			"HOME=/",
+			"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
+		},
+		container.Config.Env...,
+	)
+
 	var err error
 	if container.Config.Tty {
 		err = container.startPty()
diff --git a/sysinit.go b/sysinit.go
index c475b3365..f70141797 100644
--- a/sysinit.go
+++ b/sysinit.go
@@ -52,13 +52,6 @@ func changeUser(u string) {
 	}
 }
 
-// Set the environment to a known, repeatable state
-func setupEnv() {
-	os.Clearenv()
-	os.Setenv("HOME", "/")
-	os.Setenv("PATH", "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin")
-}
-
 func executeProgram(name string, args []string) {
 	path, err := exec.LookPath(name)
 	if err != nil {
@@ -86,6 +79,5 @@ func SysInit() {
 
 	setupNetworking(*gw)
 	changeUser(*u)
-	setupEnv()
 	executeProgram(flag.Arg(0), flag.Args())
 }