gistfile.patch

diff --git a/docs/content/commands/npm-ls.md b/docs/content/commands/npm-ls.md
index fb752742d..3c6621763 100644
--- a/docs/content/commands/npm-ls.md
+++ b/docs/content/commands/npm-ls.md
@@ -199,6 +199,16 @@ brand new workspace within the project.
 
 This value is not exported to the environment for child processes.
 
+#### `workspaces`
+
+* Default: false
+* Type: Boolean
+
+Enable running a command in the context of **all** the configured
+workspaces.
+
+This value is not exported to the environment for child processes.
+
 <!-- AUTOGENERATED CONFIG DESCRIPTIONS END -->
 
 ### See Also
diff --git a/lib/ls.js b/lib/ls.js
index 7e9e65aa8..4e504912a 100644
--- a/lib/ls.js
+++ b/lib/ls.js
@@ -50,7 +50,7 @@ class LS extends ArboristWorkspaceCmd {
       'omit',
       'link',
       'unicode',
-      'workspace',
+      ...super.params,
     ]
   }
 
@@ -90,14 +90,22 @@ class LS extends ArboristWorkspaceCmd {
     const tree = await this.initTree({arb, args })
 
     // filters by workspaces nodes when using -w <workspace-name>
-    let filterSet
+    // We only have to filter the first layer of edges, so we don't
+    // explore anything that isn't part of the selected workspace set.
+    let wsNodes
     if (this.workspaces && this.workspaces.length)
-      filterSet = arb.workspaceDependencySet(tree, this.workspaces)
+      wsNodes = arb.workspaceNodes(tree, this.workspaces)
     const filterBySelectedWorkspaces = edge => {
-      const node = edge && edge.to && (edge.to.target || edge.to)
-      return !filterSet
-        || filterSet.size === 0
-        || (node && filterSet.has(node))
+      if (!wsNodes || !wsNodes.length)
+        return true
+
+      if (edge.from.isProjectRoot) {
+        return edge.to &&
+          edge.to.isWorkspace &
+          wsNodes.includes(edge.to.target)
+      }
+
+      return true
     }
 
     const seenItems = new Set()
diff --git a/tap-snapshots/test/lib/load-all-commands.js.test.cjs b/tap-snapshots/test/lib/load-all-commands.js.test.cjs
index a1f439452..f43b761d1 100644
--- a/tap-snapshots/test/lib/load-all-commands.js.test.cjs
+++ b/tap-snapshots/test/lib/load-all-commands.js.test.cjs
@@ -539,6 +539,8 @@ Options:
 [-a|--all] [--json] [-l|--long] [-p|--parseable] [-g|--global] [--depth <depth>]
 [--omit <dev|optional|peer> [--omit <dev|optional|peer> ...]] [--link]
 [--unicode]
+[-w|--workspace <workspace-name> [-w|--workspace <workspace-name> ...]]
+[-ws|--workspaces]
 
 alias: la
 
@@ -587,6 +589,8 @@ Options:
 [-a|--all] [--json] [-l|--long] [-p|--parseable] [-g|--global] [--depth <depth>]
 [--omit <dev|optional|peer> [--omit <dev|optional|peer> ...]] [--link]
 [--unicode]
+[-w|--workspace <workspace-name> [-w|--workspace <workspace-name> ...]]
+[-ws|--workspaces]
 
 alias: list
 
diff --git a/tap-snapshots/test/lib/utils/npm-usage.js.test.cjs b/tap-snapshots/test/lib/utils/npm-usage.js.test.cjs
index 776492c4d..f7fd7ccba 100644
--- a/tap-snapshots/test/lib/utils/npm-usage.js.test.cjs
+++ b/tap-snapshots/test/lib/utils/npm-usage.js.test.cjs
@@ -641,6 +641,7 @@ All commands:
                     [--omit <dev|optional|peer> [--omit <dev|optional|peer> ...]] [--link]
                     [--unicode]
                     [-w|--workspace <workspace-name> [-w|--workspace <workspace-name> ...]]
+                    [-ws|--workspaces]
                     
                     alias: la
                     
@@ -684,6 +685,7 @@ All commands:
                     [--omit <dev|optional|peer> [--omit <dev|optional|peer> ...]] [--link]
                     [--unicode]
                     [-w|--workspace <workspace-name> [-w|--workspace <workspace-name> ...]]
+                    [-ws|--workspaces]
                     
                     alias: list