diff --git a/tests/integration_tests.rs b/tests/integration_tests.rs
new file mode 100644
index 0000000..a3ebfca
--- /dev/null
+++ b/tests/integration_tests.rs
@@ -0,0 +1,418 @@
+use assert_cmd::prelude::*;
+use predicates::prelude::*;
+use std::process::Command;
+use std::fs;
+use std::path::PathBuf;
+
+fn get_test_vault_path() -> PathBuf {
+    PathBuf::from("/tmp/api-token-vault-test-vault.json")
+}
+
+fn cleanup_test_vault() {
+    let vault_path = get_test_vault_path();
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+}
+
+#[test]
+fn test_cli_help() {
+    let mut cmd = Command::cargo_bin("api-token-vault").unwrap();
+    cmd.arg("--help");
+    cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("API Token Vault"));
+}
+
+#[test]
+fn test_cli_version() {
+    let mut cmd = Command::cargo_bin("api-token-vault").unwrap();
+    cmd.arg("--version");
+    cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("0.1.0"));
+}
+
+#[test]
+fn test_init_command() {
+    cleanup_test_vault();
+    
+    let mut cmd = Command::cargo_bin("api-token-vault").unwrap();
+    cmd.arg("init")
+        .arg("--project")
+        .arg("test-init-project")
+        .env("API_VAULT_PROJECT", "");
+    
+    let assert = cmd.assert();
+    
+    cleanup_test_vault();
+}
+
+#[test]
+fn test_generate_command() {
+    cleanup_test_vault();
+    
+    let password = "test_password_123";
+    let project = "test-gen-project";
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-gen-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut gen_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    gen_cmd.arg("generate")
+        .arg("--name")
+        .arg("test_token")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    gen_cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("Generated token"));
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+}
+
+#[test]
+fn test_list_command() {
+    cleanup_test_vault();
+    
+    let password = "test_password";
+    let project = "test-list-project";
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-list-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut list_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    list_cmd.arg("list")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    list_cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("Tokens in vault"));
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+}
+
+#[test]
+fn test_rotate_command() {
+    cleanup_test_vault();
+    
+    let password = "test_password";
+    let project = "test-rotate-project";
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-rotate-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut gen_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    gen_cmd.arg("generate")
+        .arg("--name")
+        .arg("rotate_me")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = gen_cmd.output();
+    
+    let mut rotate_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    rotate_cmd.arg("rotate")
+        .arg("--name")
+        .arg("rotate_me")
+        .arg("--force")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    rotate_cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("Rotated token"));
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+}
+
+#[test]
+fn test_set_rotation_command() {
+    cleanup_test_vault();
+    
+    let password = "test_password";
+    let project = "test-set-rotation-project";
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-set-rotation-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut gen_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    gen_cmd.arg("generate")
+        .arg("--name")
+        .arg("auto_rotate_token")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = gen_cmd.output();
+    
+    let mut set_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    set_cmd.arg("set-rotation")
+        .arg("--name")
+        .arg("auto_rotate_token")
+        .arg("--days")
+        .arg("30")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    set_cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("Auto-rotation set"));
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+}
+
+#[test]
+fn test_check_expired_command() {
+    cleanup_test_vault();
+    
+    let password = "test_password";
+    let project = "test-check-expired-project";
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-check-expired-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut gen_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    gen_cmd.arg("generate")
+        .arg("--name")
+        .arg("expired_token")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = gen_cmd.output();
+    
+    let mut check_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    check_cmd.arg("check-expired")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    check_cmd.assert()
+        .success();
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+}
+
+#[test]
+fn test_inject_command() {
+    cleanup_test_vault();
+    
+    let password = "test_password";
+    let project = "test-inject-project";
+    let env_path = PathBuf::from("/tmp/test-inject.env");
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-inject-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    if env_path.exists() {
+        let _ = fs::remove_file(&env_path);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut gen_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    gen_cmd.arg("generate")
+        .arg("--name")
+        .arg("injectable_token")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = gen_cmd.output();
+    
+    let mut inject_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    inject_cmd.arg("inject")
+        .arg("--env-file")
+        .arg(env_path.to_str().unwrap())
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    inject_cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("injected"));
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if env_path.exists() {
+        let _ = fs::remove_file(&env_path);
+    }
+}
+
+#[test]
+fn test_dry_run_inject() {
+    cleanup_test_vault();
+    
+    let password = "test_password";
+    let project = "test-dry-run-project";
+    let env_path = PathBuf::from("/tmp/test-dry-run.env");
+    
+    let vault_dir = PathBuf::from("/tmp/.config/api-token-vault");
+    let vault_path = vault_dir.join("test-dry-run-project.json");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if !vault_dir.exists() {
+        let _ = fs::create_dir_all(&vault_dir);
+    }
+    if env_path.exists() {
+        let _ = fs::remove_file(&env_path);
+    }
+    
+    let mut init_cmd = Command::cargo_bin("token-vault").unwrap();
+    init_cmd.arg("init")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = init_cmd.output();
+    
+    let mut gen_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    gen_cmd.arg("generate")
+        .arg("--name")
+        .arg("dry_token")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    let _ = gen_cmd.output();
+    
+    fs::write(&env_path, "EXISTING=value").unwrap();
+    
+    let mut inject_cmd = Command::cargo_bin("api-token-vault").unwrap();
+    inject_cmd.arg("inject")
+        .arg("--env-file")
+        .arg(env_path.to_str().unwrap())
+        .arg("--dry-run")
+        .arg("--master-password")
+        .arg(password)
+        .arg("--project")
+        .arg(project);
+    
+    inject_cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("Dry run"));
+    
+    let content = fs::read_to_string(&env_path).unwrap();
+    assert_eq!(content.trim(), "EXISTING=value");
+    
+    if vault_path.exists() {
+        let _ = fs::remove_file(&vault_path);
+    }
+    if env_path.exists() {
+        let _ = fs::remove_file(&env_path);
+    }
+}