diff --git a/cmd/doctor.go b/cmd/doctor.go
new file mode 100644
index 0000000..1e99748
--- /dev/null
+++ b/cmd/doctor.go
@@ -0,0 +1,128 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+)
+
+var doctorCmd = &cobra.Command{
+	Use:          "doctor",
+	Short:        "Check environment health",
+	RunE:         doctor,
+	SilenceUsage: true,
+}
+
+func init() {
+	rootCmd.AddCommand(doctorCmd)
+}
+
+func doctor(cmd *cobra.Command, args []string) error {
+	tty := stdoutIsTerminal()
+	hasError := false
+
+	emit := func(level, msg string) {
+		var code string
+		switch level {
+		case "ok":
+			code = "32"
+		case "info":
+			code = "34"
+		case "FAIL":
+			code = "31"
+			hasError = true
+		}
+		fmt.Fprintf(os.Stdout, "%s  %s\n", keyword(code, level, tty), msg)
+	}
+
+	// Config
+	cfgPath, err := configPath()
+	if err != nil {
+		emit("FAIL", fmt.Sprintf("Cannot determine config path: %v", err))
+	} else if _, err := os.Stat(cfgPath); os.IsNotExist(err) {
+		emit("info", "Using default configuration")
+	} else if err != nil {
+		emit("FAIL", fmt.Sprintf("Cannot access config: %v", err))
+	} else {
+		emit("ok", "Configuration loaded")
+	}
+
+	// Data directory
+	store := &Store{}
+	dataDir, err := store.path()
+	if err != nil {
+		emit("FAIL", fmt.Sprintf("Data directory inaccessible: %v", err))
+	} else {
+		emit("ok", "Data directory accessible")
+	}
+
+	// Identity
+	idPath, err := identityPath()
+	if err != nil {
+		emit("FAIL", fmt.Sprintf("Cannot determine identity path: %v", err))
+	} else if _, err := os.Stat(idPath); os.IsNotExist(err) {
+		emit("info", "No identity file. One will be created on first encrypt.")
+	} else if err != nil {
+		emit("FAIL", fmt.Sprintf("Cannot access identity file: %v", err))
+	} else {
+		emit("ok", "Identity file present")
+	}
+
+	// Git
+	gitInitialised := false
+	if dataDir != "" {
+		gitDir := filepath.Join(dataDir, ".git")
+		if _, err := os.Stat(gitDir); os.IsNotExist(err) {
+			emit("info", "Git not initialised")
+		} else if err != nil {
+			emit("FAIL", fmt.Sprintf("Cannot check git status: %v", err))
+		} else {
+			gitInitialised = true
+			emit("ok", "Git initialised")
+		}
+	}
+
+	// Git remote (only when git is initialised)
+	if gitInitialised {
+		hasOrigin, err := repoHasRemote(dataDir, "origin")
+		if err != nil {
+			emit("FAIL", fmt.Sprintf("Cannot check git remote: %v", err))
+		} else if hasOrigin {
+			emit("ok", "Git remote configured")
+		} else {
+			emit("info", "No git remote configured")
+		}
+	}
+
+	// Stores
+	stores, err := store.AllStores()
+	if err != nil {
+		emit("FAIL", fmt.Sprintf("Cannot list stores: %v", err))
+	} else if len(stores) == 0 {
+		emit("info", "No stores")
+	} else {
+		var parseErrors int
+		for _, name := range stores {
+			p, pErr := store.storePath(name)
+			if pErr != nil {
+				parseErrors++
+				continue
+			}
+			if _, rErr := readStoreFile(p, nil); rErr != nil {
+				parseErrors++
+			}
+		}
+		if parseErrors > 0 {
+			emit("FAIL", fmt.Sprintf("%d store(s), %d with errors", len(stores), parseErrors))
+		} else {
+			emit("ok", fmt.Sprintf("%d store(s)", len(stores)))
+		}
+	}
+
+	if hasError {
+		os.Exit(1)
+	}
+	return nil
+}
diff --git a/testdata/doctor.ct b/testdata/doctor.ct
new file mode 100644
index 0000000..0495da5
--- /dev/null
+++ b/testdata/doctor.ct
@@ -0,0 +1,7 @@
+# Doctor reports environment health
+$ pda doctor
+info  Using default configuration
+  ok  Data directory accessible
+  ok  Identity file present
+info  Git not initialised
+  ok  5 store(s)
diff --git a/testdata/help.ct b/testdata/help.ct
index c511e94..5df93df 100644
--- a/testdata/help.ct
+++ b/testdata/help.ct
@@ -36,6 +36,7 @@ Git commands:
 
 Additional Commands:
   completion   Generate the autocompletion script for the specified shell
+  doctor       Check environment health
   help         Help about any command
   version      Display pda! version
 
@@ -79,6 +80,7 @@ Git commands:
 
 Additional Commands:
   completion   Generate the autocompletion script for the specified shell
+  doctor       Check environment health
   help         Help about any command
   version      Display pda! version
 
diff --git a/testdata/root.ct b/testdata/root.ct
index 3b6911d..6e049e0 100644
--- a/testdata/root.ct
+++ b/testdata/root.ct
@@ -35,6 +35,7 @@ Git commands:
 
 Additional Commands:
   completion   Generate the autocompletion script for the specified shell
+  doctor       Check environment health
   help         Help about any command
   version      Display pda! version