diff --git a/cmd/mg/cmd/register.go b/cmd/mg/cmd/register.go
index 3160b6c..0026174 100644
--- a/cmd/mg/cmd/register.go
+++ b/cmd/mg/cmd/register.go
@@ -20,6 +20,9 @@ var registerCmd = &cobra.Command{
 		}
 		if len(args) == 1 {
 			path = args[0]
+		} else if len(args) > 1 {
+			log.Println("too many arguments")
+			os.Exit(1)
 		}
 		r, err := git.PlainOpenWithOptions(path, &(git.PlainOpenOptions{DetectDotGit: true}))
 		if err != nil {
diff --git a/cmd/mg/cmd/unregister.go b/cmd/mg/cmd/unregister.go
index 223f97c..70386a1 100644
--- a/cmd/mg/cmd/unregister.go
+++ b/cmd/mg/cmd/unregister.go
@@ -1,17 +1,57 @@
 package cmd
 
 import (
-	"fmt"
+	"log"
+	"os"
 
+	git "github.com/go-git/go-git/v5"
 	"github.com/spf13/cobra"
 )
 
 // unregisterCmd represents the unregister command
 var unregisterCmd = &cobra.Command{
 	Use:   "unregister",
-	Short: "remove the current repo from the config",
-	Run: func(cmd *cobra.Command, args []string) {
-		fmt.Println("unregister called")
+	Short: "add current path to list of repos",
+	Run: func(_ *cobra.Command, args []string) {
+		conf := GetConfig()
+		path, err := os.Getwd()
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		if len(args) == 1 {
+			path = args[0]
+			err = conf.DelRepo(path)
+			if err != nil {
+				log.Println(err)
+				os.Exit(1)
+			}
+			return
+		} else if len(args) > 1 {
+			log.Println("too many arguments")
+			os.Exit(1)
+		}
+		r, err := git.PlainOpenWithOptions(path, &(git.PlainOpenOptions{DetectDotGit: true}))
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		newPath, err := r.Worktree()
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		path = newPath.Filesystem.Root()
+		err = conf.DelRepo(path)
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		err = conf.Save()
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
 	},
 }
 
diff --git a/parse/mgconf.go b/parse/mgconf.go
index d24eb2a..4a3cedb 100644
--- a/parse/mgconf.go
+++ b/parse/mgconf.go
@@ -7,6 +7,8 @@ import (
 	"path/filepath"
 )
 
+var errAlreadyRegistered = os.ErrExist
+
 // MGConfig is the struct that represents the mgconfig file
 // It contains a slice of Repo structs and a map of aliases
 // The aliases map is a map of strings to strings, where the key is the alias
@@ -27,8 +29,25 @@ func (m MGConfig) GetRepoPaths() []string {
 	return paths
 }
 
-func (m *MGConfig) AddRepo(path, remote string) {
+func (m *MGConfig) DelRepo(path string) error {
+	for i, v := range m.Repos {
+		if v.Path == path {
+			m.Repos = append(m.Repos[:i], m.Repos[i+1:]...)
+			return nil
+		}
+	}
+	return os.ErrNotExist
+}
+
+func (m *MGConfig) AddRepo(path, remote string) error {
+	for _, v := range m.Repos {
+		if v.Path == path {
+			return errAlreadyRegistered
+		}
+	}
+
 	m.Repos = append(m.Repos, Repo{Path: path, Remote: remote})
+	return nil
 }
 
 // LoadMGConfig loads the mgconfig file from the XDG_CONFIG_HOME directory