diff --git a/README.md b/README.md
index e797cf17..52032ecb 100644
--- a/README.md
+++ b/README.md
@@ -66,6 +66,16 @@ pnpm install
 scip-typescript index --pnpm-workspaces
 ```
 
+### Index a TypeScript project using npm workspaces
+
+Navigate to the project root, containing `package.json` with a `workspaces` field.
+
+```sh
+npm install
+
+scip-typescript index --npm-workspaces
+```
+
 ### Indexing in CI
 
 Add the following run steps to your CI pipeline:
diff --git a/snapshots/input/npm-workspaces/package.json b/snapshots/input/npm-workspaces/package.json
new file mode 100644
index 00000000..32e3e5ed
--- /dev/null
+++ b/snapshots/input/npm-workspaces/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "npm-workspaces",
+  "version": "1.0.0",
+  "description": "Example TS/JS project",
+  "main": "src/main.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "ISC",
+  "private": true,
+  "packageManager": "npm@10.0.0",
+  "workspaces": [
+    "packages/*"
+  ]
+}
diff --git a/snapshots/input/npm-workspaces/packages/a/package.json b/snapshots/input/npm-workspaces/packages/a/package.json
new file mode 100644
index 00000000..0c881692
--- /dev/null
+++ b/snapshots/input/npm-workspaces/packages/a/package.json
@@ -0,0 +1,11 @@
+{
+  "name": "@example/a",
+  "version": "1.0.0",
+  "description": "Example TS/JS project",
+  "main": "src/a.ts",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "ISC"
+}
diff --git a/snapshots/input/npm-workspaces/packages/a/src/a.ts b/snapshots/input/npm-workspaces/packages/a/src/a.ts
new file mode 100644
index 00000000..f7534476
--- /dev/null
+++ b/snapshots/input/npm-workspaces/packages/a/src/a.ts
@@ -0,0 +1,3 @@
+export function a(): string {
+  return ''
+}
diff --git a/snapshots/input/npm-workspaces/packages/a/tsconfig.json b/snapshots/input/npm-workspaces/packages/a/tsconfig.json
new file mode 100644
index 00000000..6950116c
--- /dev/null
+++ b/snapshots/input/npm-workspaces/packages/a/tsconfig.json
@@ -0,0 +1,9 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "baseUrl": ".",
+    "outDir": "dist"
+  },
+  "include": ["src/*"]
+}
diff --git a/snapshots/input/npm-workspaces/packages/b/package.json b/snapshots/input/npm-workspaces/packages/b/package.json
new file mode 100644
index 00000000..28b64d44
--- /dev/null
+++ b/snapshots/input/npm-workspaces/packages/b/package.json
@@ -0,0 +1,14 @@
+{
+  "name": "@example/b",
+  "version": "1.0.0",
+  "description": "Example TS/JS project",
+  "main": "src/b.ts",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "@example/a": "1.0.0"
+  }
+}
diff --git a/snapshots/input/npm-workspaces/packages/b/src/b.ts b/snapshots/input/npm-workspaces/packages/b/src/b.ts
new file mode 100644
index 00000000..8dcbedc0
--- /dev/null
+++ b/snapshots/input/npm-workspaces/packages/b/src/b.ts
@@ -0,0 +1,5 @@
+import { a } from '@example/a'
+
+export function b() {
+  return a()
+}
diff --git a/snapshots/input/npm-workspaces/packages/b/tsconfig.json b/snapshots/input/npm-workspaces/packages/b/tsconfig.json
new file mode 100644
index 00000000..61cd48e2
--- /dev/null
+++ b/snapshots/input/npm-workspaces/packages/b/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "baseUrl": "./src",
+    "sourceRoot": "src",
+    "outDir": "dist",
+    "paths": {
+      "@example/a": ["../../a/src/a.ts"]
+    }
+  },
+  "include": ["src/*"],
+  "references": [{ "path": "../a" }]
+}
diff --git a/snapshots/input/npm-workspaces/tsconfig.json b/snapshots/input/npm-workspaces/tsconfig.json
new file mode 100644
index 00000000..ae727a12
--- /dev/null
+++ b/snapshots/input/npm-workspaces/tsconfig.json
@@ -0,0 +1,24 @@
+{
+  "extends": "@sourcegraph/tsconfig",
+  "compilerOptions": {
+    "target": "es2020",
+    "module": "commonjs",
+    "allowJs": false,
+    "moduleResolution": "node",
+    "esModuleInterop": true,
+    "lib": ["esnext", "dom", "dom.iterable"],
+    "sourceMap": true,
+    "declaration": true,
+    "declarationMap": true,
+    "skipLibCheck": true,
+    "skipDefaultLibCheck": true,
+    "noErrorTruncation": true,
+    "importHelpers": true,
+    "resolveJsonModule": true,
+    "composite": true,
+    "outDir": "out",
+    "rootDir": "."
+  },
+  "include": [],
+  "exclude": ["out", "node_modules", "dist"]
+}
diff --git a/snapshots/output/npm-workspaces/packages/a/src/a.ts b/snapshots/output/npm-workspaces/packages/a/src/a.ts
new file mode 100644
index 00000000..b04e75fd
--- /dev/null
+++ b/snapshots/output/npm-workspaces/packages/a/src/a.ts
@@ -0,0 +1,8 @@
+// language TypeScript
+// < definition @example/a 1.0.0 src/`a.ts`/
+
+export function a(): string {
+//              ^ definition @example/a 1.0.0 src/`a.ts`/a().
+  return ''
+}
+
diff --git a/snapshots/output/npm-workspaces/packages/b/src/b.ts b/snapshots/output/npm-workspaces/packages/b/src/b.ts
new file mode 100644
index 00000000..b5efc02a
--- /dev/null
+++ b/snapshots/output/npm-workspaces/packages/b/src/b.ts
@@ -0,0 +1,13 @@
+// language TypeScript
+// < definition @example/b 1.0.0 src/`b.ts`/
+
+import { a } from '@example/a'
+//       ^ reference @example/a 1.0.0 src/`a.ts`/a().
+//                ^^^^^^^^^^^^ reference @example/a 1.0.0 src/`a.ts`/
+
+export function b() {
+//              ^ definition @example/b 1.0.0 src/`b.ts`/b().
+  return a()
+//       ^ reference @example/a 1.0.0 src/`a.ts`/a().
+}
+
diff --git a/src/CommandLineOptions.test.ts b/src/CommandLineOptions.test.ts
index aed2c31c..572042c9 100644
--- a/src/CommandLineOptions.test.ts
+++ b/src/CommandLineOptions.test.ts
@@ -33,6 +33,7 @@ checkIndexParser([], {
 checkIndexParser(['--cwd', 'qux'], { cwd: 'qux' })
 checkIndexParser(['--yarn-workspaces'], { yarnWorkspaces: true })
 checkIndexParser(['--pnpm-workspaces'], { pnpmWorkspaces: true })
+checkIndexParser(['--npm-workspaces'], { npmWorkspaces: true })
 checkIndexParser(['--infer-tsconfig'], { inferTsconfig: true })
 checkIndexParser(['--no-progress-bar'], { progressBar: false })
 checkIndexParser(['--progress-bar'], { progressBar: true })
diff --git a/src/CommandLineOptions.ts b/src/CommandLineOptions.ts
index 4892586f..6173c245 100644
--- a/src/CommandLineOptions.ts
+++ b/src/CommandLineOptions.ts
@@ -14,6 +14,7 @@ export interface MultiProjectOptions {
   yarnWorkspaces: boolean
   yarnBerryWorkspaces: boolean
   pnpmWorkspaces: boolean
+  npmWorkspaces: boolean
   globalCaches: boolean
   maxFileByteSize?: string
   maxFileByteSizeNumber?: number
@@ -54,6 +55,7 @@ export function mainCommand(
     .command('index')
     .option('--cwd <path>', 'the working directory', process.cwd())
     .option('--pnpm-workspaces', 'whether to index all pnpm workspaces', false)
+    .option('--npm-workspaces', 'whether to index all npm workspaces', false)
     .option('--yarn-workspaces', 'whether to index all yarn workspaces', false)
     .option(
       '--yarn-berry-workspaces',
diff --git a/src/FileIndexer.test.ts b/src/FileIndexer.test.ts
index ea8c7312..50c5294b 100644
--- a/src/FileIndexer.test.ts
+++ b/src/FileIndexer.test.ts
@@ -35,6 +35,7 @@ test('local prototype owners stay out of the global symbol table', () => {
       yarnWorkspaces: false,
       yarnBerryWorkspaces: false,
       pnpmWorkspaces: false,
+      npmWorkspaces: false,
       globalCaches: true,
       indexedProjects: new Set(),
       writeIndex: () => {},
@@ -88,6 +89,7 @@ test('lone surrogates in documentation and symbols survive serialization', () =>
       yarnWorkspaces: false,
       yarnBerryWorkspaces: false,
       pnpmWorkspaces: false,
+      npmWorkspaces: false,
       globalCaches: true,
       indexedProjects: new Set(),
       writeIndex: () => {},
diff --git a/src/ProjectIndexer.test.ts b/src/ProjectIndexer.test.ts
index 5df7f843..129450de 100644
--- a/src/ProjectIndexer.test.ts
+++ b/src/ProjectIndexer.test.ts
@@ -80,6 +80,7 @@ test('only deduplicates documents after successful emission', () => {
       yarnWorkspaces: false,
       yarnBerryWorkspaces: false,
       pnpmWorkspaces: false,
+      npmWorkspaces: false,
       globalCaches: false,
       indexedProjects: new Set(),
       writeIndex: () => {
diff --git a/src/Svelte.test.ts b/src/Svelte.test.ts
index a82c2c92..4d7a3a68 100644
--- a/src/Svelte.test.ts
+++ b/src/Svelte.test.ts
@@ -151,6 +151,7 @@ test('no-global-caches keeps Svelte source information project-local', () => {
       yarnWorkspaces: false,
       yarnBerryWorkspaces: false,
       pnpmWorkspaces: false,
+      npmWorkspaces: false,
       globalCaches: false,
       indexedProjects: new Set(),
       writeIndex: index => documents.push(...index.documents),
diff --git a/src/main.test.ts b/src/main.test.ts
index 4a0076ee..0a509399 100644
--- a/src/main.test.ts
+++ b/src/main.test.ts
@@ -90,13 +90,15 @@ for (const snapshotDirectory of snapshotDirectories) {
     const tsconfigJsonPath = path.join(inputRoot, 'tsconfig.json')
     const inferTsconfig = !fs.existsSync(tsconfigJsonPath)
     const output = path.join(inputRoot, 'index.scip')
+    const isNpm = Boolean(packageJson.packageManager?.startsWith('npm@'))
     indexCommand([], {
       cwd: inputRoot,
       inferTsconfig,
       output,
-      yarnWorkspaces: Boolean(packageJson.workspaces),
+      yarnWorkspaces: Boolean(packageJson.workspaces) && !isNpm,
       yarnBerryWorkspaces: false,
       pnpmWorkspaces: Boolean(packageJson.packageManager?.includes('pnpm')),
+      npmWorkspaces: isNpm,
       progressBar: false,
       indexedProjects: new Set(),
       globalCaches: true,
diff --git a/src/main.ts b/src/main.ts
index 90dc05c4..f107fa99 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -44,6 +44,8 @@ export function indexCommand(
     projects.push(...listYarnWorkspaces(options.cwd, 'yarn2Plus'))
   } else if (options.pnpmWorkspaces) {
     projects.push(...listPnpmWorkspaces(options.cwd))
+  } else if (options.npmWorkspaces) {
+    projects.push(...listNpmWorkspaces(options.cwd))
   } else if (projects.length === 0) {
     projects.push(options.cwd)
   }
@@ -251,6 +253,21 @@ function defaultCompilerOptions(configFileName?: string): ts.CompilerOptions {
   return options
 }
 
+function listNpmWorkspaces(directory: string): string[] {
+  const { workspaces = [] } = JSON.parse(
+    fs.readFileSync(path.join(directory, 'package.json'), 'utf-8')
+  ) as { workspaces?: string[] | { packages?: string[] } }
+  const patterns = Array.isArray(workspaces)
+    ? workspaces
+    : (workspaces.packages ?? [])
+  return fs
+    .globSync(
+      patterns.map(pattern => path.posix.join(pattern, 'package.json')),
+      { cwd: directory, exclude: name => name === 'node_modules' }
+    )
+    .map(packageJsonPath => path.join(directory, path.dirname(packageJsonPath)))
+}
+
 function listPnpmWorkspaces(directory: string): string[] {
   /**
    * Returns the list of projects formatted as: