Windows & Projects

How Zed handles multiple projects in windows, including the threads sidebar and options for opening in new windows.

Zed lets you work on multiple projects in a single window. Projects appear in the threads sidebar on the left, and you can switch between them while keeping your context intact.

Use Panel Layout > Agentic from the user menu in the title bar (or the workspace::UseAgenticLayout action) to keep the Threads Sidebar and Agent Panel together on the left. Use Panel Layout > Classic (or workspace::UseClassicLayout) to restore the editor-oriented layout.

How Projects Open

By default, when you open a folder in Zed, it opens as a new project in your current window's threads sidebar rather than creating a new window. This keeps related work together and preserves your agent threads and layout.

Action	Result
File > Open	Opens in current window (threads sidebar)
File > Open Recent	Opens in current window (threads sidebar)
Drag folder to Zed	Opens in current window (threads sidebar)
`zed ~/project`	Opens in current window (threads sidebar)

Working with Multiple Projects

When you have multiple projects open:

Click a project header to collapse or expand its threads; Cmd+click (macOS) or Ctrl+click (Linux/Windows) to switch to that project
Each project has its own file tree, git state, and search scope
Agent threads are tied to their project context
Your workspace layout (splits, tabs) is preserved per project

Think of projects in the threads sidebar like browser tabs, but for repositories.

Opening in a New Window

Sometimes you want a completely separate window. Here's how:

From Open Recent

When using File > Open Recent (projects::OpenRecent):

Enter or click opens in the current window (threads sidebar)
Cmd+Enter or Cmd+click (macOS) / Ctrl+Enter or Ctrl+click (Linux/Windows) opens in a new window

From the CLI

Use the -n flag to force a new window:

zed -n ~/projects/other-project

Other CLI options for controlling window behavior:

Flag	Behavior
`-n`, `--new`	Always open in a new window
`-a`, `--add`	Add to the current window's threads sidebar
`-r`, `--reuse`	Replace the current project in the existing window

See CLI Reference for full details.

Via Settings

You can change the default behavior by setting cli_default_open_behavior, which controls CLI opens, and default_open_behavior, which controls UI project opens and external open requests, such as macOS Finder's Open With > Zed.

To use separate windows, open the Settings Editor and search for CLI Default Open Behavior or Default Open Behavior, setting either or both to new_window. Or add this to your settings.json:

{
  "default_open_behavior": "new_window",
  "cli_default_open_behavior": "new_window"
}

Both settings accept the same values:

existing_window (default): Open folders in the current window's threads sidebar. Files outside any open project can also open in an existing window.
new_window: Prefer a new window. For external or CLI file opens, a non-ignored file inside an already-open project opens in that project's window while an unrelated file opens in a new window.

It's worth noting that explicit flags provided to the CLI will override the CLI setting. In particular, -n forces a new window even when a path matches an open project. See CLI Reference for the available flags.

Adding Folders to a Project

If you want to add a folder to your current project (not as a separate project in the threads sidebar), you have several options:

File menu: File > Add Folder to Project
Project panel: Right-click in the project panel and choose "Add Folders to Project"
Open Recent: Select a recent project and click the "Add Folder to this Project" button

This adds the folder as an additional root in your current project's file tree, similar to VS Code's multi-root workspaces.