diff --git a/README.md b/README.md
index fe6cad0..515bdb7 100644
--- a/README.md
+++ b/README.md
@@ -21,3 +21,4 @@
     - [ ] Positional variables
     - [ ] `RANDOM`
 - [ ] Handle signals
+- [x] Handle when command is not found
diff --git a/src/buffer.rs b/src/buffer.rs
index 9424734..ceab8ae 100644
--- a/src/buffer.rs
+++ b/src/buffer.rs
@@ -2,6 +2,7 @@ use std::io as stdio;
 use stdio::stdin;
 use crate::parser;
 use crate::job;
+use crate::error::command_not_found;
 
 pub struct Buffer {
     buffer: String,
@@ -34,6 +35,7 @@ impl Buffer {
     pub fn try_spawn(&mut self) -> Option<i32> {
         if ! self.buffer.is_empty() {
             self.argv = parser::parse(&self.buffer);
+            let command_name = self.argv[0].to_string();
             let result = job::execute(&mut self.argv);
 
             if result.is_ok() {
@@ -43,8 +45,7 @@ impl Buffer {
                     return Some(result.code().unwrap());
                 }
             } else {
-                eprintln!("{}", result.unwrap_err());
-                return Some(127);
+                return Some(command_not_found(&command_name));
             }
         }
 
diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..b51b2a3
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,18 @@
+use std::env;
+use std::path::Path;
+
+fn error(message: &str) {
+    let argv0: String = env::args().next().unwrap();
+    let program_name = Path::new(&argv0)
+        .file_name()
+        .unwrap()
+        .to_str()
+        .unwrap();
+    eprintln!("{}: {}", program_name, message);
+}
+
+pub fn command_not_found(command: &String) -> i32 {
+    let message = command.to_owned() + ": command not found";
+    error(&message);
+    127
+}
diff --git a/src/main.rs b/src/main.rs
index 67b8fda..ced5470 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,6 +2,7 @@ mod buffer;
 mod parser;
 mod job;
 mod variables;
+mod error;
 
 use std::process::exit;
 use variables::Variables;