diff --git a/src/poetry_slam/cli.py b/src/poetry_slam/cli.py
index c294f2e..538c446 100644
--- a/src/poetry_slam/cli.py
+++ b/src/poetry_slam/cli.py
@@ -78,10 +78,11 @@ def new(
     """
     Initialize a project with boilerplate code.
     """
+    package_name = project_name.lower().replace('-', '_')
     tmpl = templates()[template.name]
     tmpl.values = {
         'PROJECT_NAME': project_name,
-        'PACKAGE_NAME': project_name,
+        'PACKAGE_NAME': package_name,
         'DESCRIPTION': f"{project_name}: automatically generated by poetry-slam.",
         'AUTHOR_NAME': os.environ['USER']
     }